-
One physical core (IFL) provides two logical cores (threads) when SMT-2 is enabled. The hypervisor can provide two or more vCPUs.
In OpenShift Container Platform version 4.15, you can install a cluster on IBM Z® or IBM® LinuxONE infrastructure that you provision.
While this document refers only to IBM Z®, all information in it also applies to IBM® LinuxONE. |
Additional considerations exist for non-bare metal platforms. Review the information in the guidelines for deploying OpenShift Container Platform on non-tested platforms before you install an OpenShift Container Platform cluster. |
You reviewed details about the OpenShift Container Platform installation and update processes.
You read the documentation on selecting a cluster installation method and preparing it for users.
Before you begin the installation process, you must clean the installation directory. This ensures that the required installation files are created and updated during the installation process.
You provisioned persistent storage using OpenShift Data Foundation or other supported storage protocols for your cluster. To deploy a private image registry, you must set up persistent storage with ReadWriteMany
access.
If you use a firewall, you configured it to allow the sites that your cluster requires access to.
Be sure to also review this site list if you are configuring a proxy. |
In OpenShift Container Platform 4.15, you require access to the internet to install your cluster.
You must have internet access to:
Access OpenShift Cluster Manager to download the installation program and perform subscription management. If the cluster has internet access and you do not disable Telemetry, that service automatically entitles your cluster.
Access Quay.io to obtain the packages that are required to install your cluster.
Obtain the packages that are required to perform cluster updates.
If your cluster cannot have direct internet access, you can perform a restricted network installation on some types of infrastructure that you provision. During that process, you download the required content and use it to populate a mirror registry with the installation packages. With some installation types, the environment that you install your cluster in will not require internet access. Before you update the cluster, you update the content of the mirror registry. |
For a cluster that contains user-provisioned infrastructure, you must deploy all of the required machines.
This section describes the requirements for deploying OpenShift Container Platform on user-provisioned infrastructure.
The smallest OpenShift Container Platform clusters require the following hosts:
Hosts | Description |
---|---|
One temporary bootstrap machine |
The cluster requires the bootstrap machine to deploy the OpenShift Container Platform cluster on the three control plane machines. You can remove the bootstrap machine after you install the cluster. |
Three control plane machines |
The control plane machines run the Kubernetes and OpenShift Container Platform services that form the control plane. |
At least two compute machines, which are also known as worker machines. |
The workloads requested by OpenShift Container Platform users run on the compute machines. |
To improve high availability of your cluster, distribute the control plane machines over different z/VM instances on at least two physical machines. |
The bootstrap, control plane, and compute machines must use Red Hat Enterprise Linux CoreOS (RHCOS) as the operating system.
Note that RHCOS is based on Red Hat Enterprise Linux (RHEL) 9.2 and inherits all of its hardware certifications and requirements. See Red Hat Enterprise Linux technology capabilities and limits.
Each cluster machine must meet the following minimum requirements:
Machine | Operating System | vCPU [1] | Virtual RAM | Storage | Input/Output Per Second (IOPS) |
---|---|---|---|---|---|
Bootstrap |
RHCOS |
4 |
16 GB |
100 GB |
N/A |
Control plane |
RHCOS |
4 |
16 GB |
100 GB |
N/A |
Compute |
RHCOS |
2 |
8 GB |
100 GB |
N/A |
One physical core (IFL) provides two logical cores (threads) when SMT-2 is enabled. The hypervisor can provide two or more vCPUs.
As of OpenShift Container Platform version 4.13, RHCOS is based on RHEL version 9.2, which updates the micro-architecture requirements. The following list contains the minimum instruction set architectures (ISA) that each architecture requires:
For more information, see RHEL Architectures. |
If an instance type for your platform meets the minimum requirements for cluster machines, it is supported to use in OpenShift Container Platform.
You can install OpenShift Container Platform version 4.15 on the following IBM® hardware:
IBM® z16 (all models), IBM® z15 (all models), IBM® z14 (all models)
IBM® LinuxONE 4 (all models), IBM® LinuxONE III (all models), IBM® LinuxONE Emperor II, IBM® LinuxONE Rockhopper II
The equivalent of six Integrated Facilities for Linux (IFL), which are SMT2 enabled, for each cluster.
At least one network connection to both connect to the LoadBalancer
service and to serve data for traffic outside the cluster.
You can use dedicated or shared IFLs to assign sufficient compute resources. Resource sharing is one of the key strengths of IBM Z®. However, you must adjust capacity correctly on each hypervisor layer and ensure sufficient resources for every OpenShift Container Platform cluster. |
Since the overall performance of the cluster can be impacted, the LPARs that are used to set up the OpenShift Container Platform clusters must provide sufficient compute capacity. In this context, LPAR weight management, entitlements, and CPU shares on the hypervisor level play an important role. |
One instance of z/VM 7.2 or later
On your z/VM instance, set up:
Three guest virtual machines for OpenShift Container Platform control plane machines
Two guest virtual machines for OpenShift Container Platform compute machines
One guest virtual machine for the temporary OpenShift Container Platform bootstrap machine
To install on IBM Z® under z/VM, you require a single z/VM virtual NIC in layer 2 mode. You also need:
A direct-attached OSA or RoCE network adapter
A z/VM VSwitch set up. For a preferred setup, use OSA link aggregation.
FICON attached disk storage (DASDs). These can be z/VM minidisks, fullpack minidisks, or dedicated DASDs, all of which must be formatted as CDL, which is the default. To reach the minimum required DASD size for Red Hat Enterprise Linux CoreOS (RHCOS) installations, you need extended address volumes (EAV). If available, use HyperPAV to ensure optimal performance.
FCP attached disk storage
16 GB for OpenShift Container Platform control plane machines
8 GB for OpenShift Container Platform compute machines
16 GB for the temporary OpenShift Container Platform bootstrap machine
Three LPARS that each have the equivalent of six IFLs, which are SMT2 enabled, for each cluster.
Two network connections to both connect to the LoadBalancer
service and to serve data for traffic outside the cluster.
HiperSockets that are attached to a node either directly as a device or by bridging with one z/VM VSWITCH to be transparent to the z/VM guest. To directly connect HiperSockets to a node, you must set up a gateway to the external network via a RHEL 8 guest to bridge to the HiperSockets network.
Two or three instances of z/VM 7.2 or later for high availability
On your z/VM instances, set up:
Three guest virtual machines for OpenShift Container Platform control plane machines, one per z/VM instance.
At least six guest virtual machines for OpenShift Container Platform compute machines, distributed across the z/VM instances.
One guest virtual machine for the temporary OpenShift Container Platform bootstrap machine.
To ensure the availability of integral components in an overcommitted environment, increase the priority of the control plane by using the CP command SET SHARE
. Do the same for infrastructure nodes, if they exist. See SET SHARE in IBM® Documentation.
To install on IBM Z® under z/VM, you require a single z/VM virtual NIC in layer 2 mode. You also need:
A direct-attached OSA or RoCE network adapter
A z/VM VSwitch set up. For a preferred setup, use OSA link aggregation.
FICON attached disk storage (DASDs). These can be z/VM minidisks, fullpack minidisks, or dedicated DASDs, all of which must be formatted as CDL, which is the default. To reach the minimum required DASD size for Red Hat Enterprise Linux CoreOS (RHCOS) installations, you need extended address volumes (EAV). If available, use HyperPAV to ensure optimal performance.
FCP attached disk storage
16 GB for OpenShift Container Platform control plane machines
8 GB for OpenShift Container Platform compute machines
16 GB for the temporary OpenShift Container Platform bootstrap machine
Because your cluster has limited access to automatic machine management when you use infrastructure that you provision, you must provide a mechanism for approving cluster certificate signing requests (CSRs) after installation. The kube-controller-manager
only approves the kubelet client CSRs. The machine-approver
cannot guarantee the validity of a serving certificate that is requested by using kubelet credentials because it cannot confirm that the correct machine issued the request. You must determine and implement a method of verifying the validity of the kubelet serving certificate requests and approving them.
See Bridging a HiperSockets LAN with a z/VM Virtual Switch in IBM® Documentation.
See Scaling HyperPAV alias devices on Linux guests on z/VM for performance optimization.
See Topics in LPAR performance for LPAR weight management and entitlements.
Recommended host practices for IBM Z® & IBM® LinuxONE environments
All the Red Hat Enterprise Linux CoreOS (RHCOS) machines require networking to be configured in initramfs
during boot
to fetch their Ignition config files.
During the initial boot, the machines require an HTTP or HTTPS server to establish a network connection to download their Ignition config files.
The machines are configured with static IP addresses. No DHCP server is required. Ensure that the machines have persistent IP addresses and hostnames.
The Kubernetes API server must be able to resolve the node names of the cluster machines. If the API servers and worker nodes are in different zones, you can configure a default DNS search zone to allow the API server to resolve the node names. Another supported approach is to always refer to hosts by their fully-qualified domain names in both the node objects and all DNS requests.
You must configure the network connectivity between machines to allow OpenShift Container Platform cluster components to communicate. Each machine must be able to resolve the hostnames of all other machines in the cluster.
This section provides details about the ports that are required.
In connected OpenShift Container Platform environments, all nodes are required to have internet access to pull images for platform containers and provide telemetry data to Red Hat. |
Protocol | Port | Description |
---|---|---|
ICMP |
N/A |
Network reachability tests |
TCP |
|
Metrics |
|
Host level services, including the node exporter on ports |
|
|
The default ports that Kubernetes reserves |
|
UDP |
|
VXLAN |
|
Geneve |
|
|
Host level services, including the node exporter on ports |
|
|
IPsec IKE packets |
|
|
IPsec NAT-T packets |
|
|
Network Time Protocol (NTP) on UDP port If an external NTP time server is configured, you must open UDP port |
|
TCP/UDP |
|
Kubernetes node port |
ESP |
N/A |
IPsec Encapsulating Security Payload (ESP) |
Protocol | Port | Description |
---|---|---|
TCP |
|
Kubernetes API |
Protocol | Port | Description |
---|---|---|
TCP |
|
etcd server and peer ports |
OpenShift Container Platform clusters are configured to use a public Network Time Protocol (NTP) server by default. If you want to use a local enterprise NTP server, or if your cluster is being deployed in a disconnected network, you can configure the cluster to use a specific time server. For more information, see the documentation for Configuring chrony time service.
In OpenShift Container Platform deployments, DNS name resolution is required for the following components:
The Kubernetes API
The OpenShift Container Platform application wildcard
The bootstrap, control plane, and compute machines
Reverse DNS resolution is also required for the Kubernetes API, the bootstrap machine, the control plane machines, and the compute machines.
DNS A/AAAA or CNAME records are used for name resolution and PTR records are used for reverse name resolution. The reverse records are important because Red Hat Enterprise Linux CoreOS (RHCOS) uses the reverse records to set the hostnames for all the nodes, unless the hostnames are provided by DHCP. Additionally, the reverse records are used to generate the certificate signing requests (CSR) that OpenShift Container Platform needs to operate.
The following DNS records are required for a user-provisioned OpenShift Container Platform cluster and they must be in place before installation. In each record, <cluster_name>
is the cluster name and <base_domain>
is the base domain that you specify in the install-config.yaml
file. A complete DNS record takes the form: <component>.<cluster_name>.<base_domain>.
.
Component | Record | Description | |
---|---|---|---|
Kubernetes API |
|
A DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the API load balancer. These records must be resolvable by both clients external to the cluster and from all the nodes within the cluster. |
|
|
A DNS A/AAAA or CNAME record, and a DNS PTR record, to internally identify the API load balancer. These records must be resolvable from all the nodes within the cluster.
|
||
Routes |
|
A wildcard DNS A/AAAA or CNAME record that refers to the application ingress load balancer. The application ingress load balancer targets the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default. These records must be resolvable by both clients external to the cluster and from all the nodes within the cluster. For example, |
|
Bootstrap machine |
|
A DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the bootstrap machine. These records must be resolvable by the nodes within the cluster. |
|
Control plane machines |
|
DNS A/AAAA or CNAME records and DNS PTR records to identify each machine for the control plane nodes. These records must be resolvable by the nodes within the cluster. |
|
Compute machines |
|
DNS A/AAAA or CNAME records and DNS PTR records to identify each machine for the worker nodes. These records must be resolvable by the nodes within the cluster. |
In OpenShift Container Platform 4.4 and later, you do not need to specify etcd host and SRV records in your DNS configuration. |
You can use the |
This section provides A and PTR record configuration samples that meet the DNS requirements for deploying OpenShift Container Platform on user-provisioned infrastructure. The samples are not meant to provide advice for choosing one DNS solution over another.
In the examples, the cluster name is ocp4
and the base domain is example.com
.
The following example is a BIND zone file that shows sample A records for name resolution in a user-provisioned cluster.
$TTL 1W
@ IN SOA ns1.example.com. root (
2019070700 ; serial
3H ; refresh (3 hours)
30M ; retry (30 minutes)
2W ; expiry (2 weeks)
1W ) ; minimum (1 week)
IN NS ns1.example.com.
IN MX 10 smtp.example.com.
;
;
ns1.example.com. IN A 192.168.1.5
smtp.example.com. IN A 192.168.1.5
;
helper.example.com. IN A 192.168.1.5
helper.ocp4.example.com. IN A 192.168.1.5
;
api.ocp4.example.com. IN A 192.168.1.5 (1)
api-int.ocp4.example.com. IN A 192.168.1.5 (2)
;
*.apps.ocp4.example.com. IN A 192.168.1.5 (3)
;
bootstrap.ocp4.example.com. IN A 192.168.1.96 (4)
;
control-plane0.ocp4.example.com. IN A 192.168.1.97 (5)
control-plane1.ocp4.example.com. IN A 192.168.1.98 (5)
control-plane2.ocp4.example.com. IN A 192.168.1.99 (5)
;
compute0.ocp4.example.com. IN A 192.168.1.11 (6)
compute1.ocp4.example.com. IN A 192.168.1.7 (6)
;
;EOF
1 | Provides name resolution for the Kubernetes API. The record refers to the IP address of the API load balancer. | ||
2 | Provides name resolution for the Kubernetes API. The record refers to the IP address of the API load balancer and is used for internal cluster communications. | ||
3 | Provides name resolution for the wildcard routes. The record refers to the IP address of the application ingress load balancer. The application ingress load balancer targets the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default.
|
||
4 | Provides name resolution for the bootstrap machine. | ||
5 | Provides name resolution for the control plane machines. | ||
6 | Provides name resolution for the compute machines. |
The following example BIND zone file shows sample PTR records for reverse name resolution in a user-provisioned cluster.
$TTL 1W
@ IN SOA ns1.example.com. root (
2019070700 ; serial
3H ; refresh (3 hours)
30M ; retry (30 minutes)
2W ; expiry (2 weeks)
1W ) ; minimum (1 week)
IN NS ns1.example.com.
;
5.1.168.192.in-addr.arpa. IN PTR api.ocp4.example.com. (1)
5.1.168.192.in-addr.arpa. IN PTR api-int.ocp4.example.com. (2)
;
96.1.168.192.in-addr.arpa. IN PTR bootstrap.ocp4.example.com. (3)
;
97.1.168.192.in-addr.arpa. IN PTR control-plane0.ocp4.example.com. (4)
98.1.168.192.in-addr.arpa. IN PTR control-plane1.ocp4.example.com. (4)
99.1.168.192.in-addr.arpa. IN PTR control-plane2.ocp4.example.com. (4)
;
11.1.168.192.in-addr.arpa. IN PTR compute0.ocp4.example.com. (5)
7.1.168.192.in-addr.arpa. IN PTR compute1.ocp4.example.com. (5)
;
;EOF
1 | Provides reverse DNS resolution for the Kubernetes API. The PTR record refers to the record name of the API load balancer. |
2 | Provides reverse DNS resolution for the Kubernetes API. The PTR record refers to the record name of the API load balancer and is used for internal cluster communications. |
3 | Provides reverse DNS resolution for the bootstrap machine. |
4 | Provides reverse DNS resolution for the control plane machines. |
5 | Provides reverse DNS resolution for the compute machines. |
A PTR record is not required for the OpenShift Container Platform application wildcard. |
Before you install OpenShift Container Platform, you must provision the API and application Ingress load balancing infrastructure. In production scenarios, you can deploy the API and application Ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation.
If you want to deploy the API and application Ingress load balancers with a Red Hat Enterprise Linux (RHEL) instance, you must purchase the RHEL subscription separately. |
The load balancing infrastructure must meet the following requirements:
API load balancer: Provides a common endpoint for users, both human and machine, to interact with and configure the platform. Configure the following conditions:
Layer 4 load balancing only. This can be referred to as Raw TCP or SSL Passthrough mode.
A stateless load balancing algorithm. The options vary based on the load balancer implementation.
Do not configure session persistence for an API load balancer. Configuring session persistence for a Kubernetes API server might cause performance issues from excess application traffic for your OpenShift Container Platform cluster and the Kubernetes API that runs inside the cluster. |
Configure the following ports on both the front and back of the load balancers:
Port | Back-end machines (pool members) | Internal | External | Description |
---|---|---|---|---|
|
Bootstrap and control plane. You remove the bootstrap machine from the load
balancer after the bootstrap machine initializes the cluster control plane. You
must configure the |
X |
X |
Kubernetes API server |
|
Bootstrap and control plane. You remove the bootstrap machine from the load balancer after the bootstrap machine initializes the cluster control plane. |
X |
Machine config server |
The load balancer must be configured to take a maximum of 30 seconds from the
time the API server turns off the |
Application Ingress load balancer: Provides an ingress point for application traffic flowing in from outside the cluster. A working configuration for the Ingress router is required for an OpenShift Container Platform cluster.
Configure the following conditions:
Layer 4 load balancing only. This can be referred to as Raw TCP or SSL Passthrough mode.
A connection-based or session-based persistence is recommended, based on the options available and types of applications that will be hosted on the platform.
If the true IP address of the client can be seen by the application Ingress load balancer, enabling source IP-based session persistence can improve performance for applications that use end-to-end TLS encryption. |
Configure the following ports on both the front and back of the load balancers:
Port | Back-end machines (pool members) | Internal | External | Description |
---|---|---|---|---|
|
The machines that run the Ingress Controller pods, compute, or worker, by default. |
X |
X |
HTTPS traffic |
|
The machines that run the Ingress Controller pods, compute, or worker, by default. |
X |
X |
HTTP traffic |
If you are deploying a three-node cluster with zero compute nodes, the Ingress Controller pods run on the control plane nodes. In three-node cluster deployments, you must configure your application Ingress load balancer to route HTTP and HTTPS traffic to the control plane nodes. |
This section provides an example API and application Ingress load balancer configuration that meets the load balancing requirements for user-provisioned clusters. The sample is an /etc/haproxy/haproxy.cfg
configuration for an HAProxy load balancer. The example is not meant to provide advice for choosing one load balancing solution over another.
In the example, the same load balancer is used for the Kubernetes API and application ingress traffic. In production scenarios, you can deploy the API and application ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation.
If you are using HAProxy as a load balancer and SELinux is set to |
global
log 127.0.0.1 local2
pidfile /var/run/haproxy.pid
maxconn 4000
daemon
defaults
mode http
log global
option dontlognull
option http-server-close
option redispatch
retries 3
timeout http-request 10s
timeout queue 1m
timeout connect 10s
timeout client 1m
timeout server 1m
timeout http-keep-alive 10s
timeout check 10s
maxconn 3000
listen api-server-6443 (1)
bind *:6443
mode tcp
option httpchk GET /readyz HTTP/1.0
option log-health-checks
balance roundrobin
server bootstrap bootstrap.ocp4.example.com:6443 verify none check check-ssl inter 10s fall 2 rise 3 backup (2)
server master0 master0.ocp4.example.com:6443 weight 1 verify none check check-ssl inter 10s fall 2 rise 3
server master1 master1.ocp4.example.com:6443 weight 1 verify none check check-ssl inter 10s fall 2 rise 3
server master2 master2.ocp4.example.com:6443 weight 1 verify none check check-ssl inter 10s fall 2 rise 3
listen machine-config-server-22623 (3)
bind *:22623
mode tcp
server bootstrap bootstrap.ocp4.example.com:22623 check inter 1s backup (2)
server master0 master0.ocp4.example.com:22623 check inter 1s
server master1 master1.ocp4.example.com:22623 check inter 1s
server master2 master2.ocp4.example.com:22623 check inter 1s
listen ingress-router-443 (4)
bind *:443
mode tcp
balance source
server compute0 compute0.ocp4.example.com:443 check inter 1s
server compute1 compute1.ocp4.example.com:443 check inter 1s
listen ingress-router-80 (5)
bind *:80
mode tcp
balance source
server compute0 compute0.ocp4.example.com:80 check inter 1s
server compute1 compute1.ocp4.example.com:80 check inter 1s
1 | Port 6443 handles the Kubernetes API traffic and points to the control plane machines. |
||
2 | The bootstrap entries must be in place before the OpenShift Container Platform cluster installation and they must be removed after the bootstrap process is complete. | ||
3 | Port 22623 handles the machine config server traffic and points to the control plane machines. |
||
4 | Port 443 handles the HTTPS traffic and points to the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default. |
||
5 | Port 80 handles the HTTP traffic and points to the machines that run the Ingress Controller pods. The Ingress Controller pods run on the compute machines by default.
|
If you are using HAProxy as a load balancer, you can check that the |
Before you install OpenShift Container Platform on user-provisioned infrastructure, you must prepare the underlying infrastructure.
This section provides details about the high-level steps required to set up your cluster infrastructure in preparation for an OpenShift Container Platform installation. This includes configuring IP networking and network connectivity for your cluster nodes, preparing a web server for the Ignition files, enabling the required ports through your firewall, and setting up the required DNS and load balancing infrastructure.
After preparation, your cluster infrastructure must meet the requirements outlined in the Requirements for a cluster with user-provisioned infrastructure section.
You have reviewed the OpenShift Container Platform 4.x Tested Integrations page.
You have reviewed the infrastructure requirements detailed in the Requirements for a cluster with user-provisioned infrastructure section.
Set up static IP addresses.
Set up an HTTP or HTTPS server to provide Ignition files to the cluster nodes.
Ensure that your network infrastructure provides the required network connectivity between the cluster components. See the Networking requirements for user-provisioned infrastructure section for details about the requirements.
Configure your firewall to enable the ports required for the OpenShift Container Platform cluster components to communicate. See Networking requirements for user-provisioned infrastructure section for details about the ports that are required.
By default, port Avoid using the Ingress load balancer to expose this port, because doing so might result in the exposure of sensitive information, such as statistics and metrics, related to Ingress Controllers. |
Setup the required DNS infrastructure for your cluster.
Configure DNS name resolution for the Kubernetes API, the application wildcard, the bootstrap machine, the control plane machines, and the compute machines.
Configure reverse DNS resolution for the Kubernetes API, the bootstrap machine, the control plane machines, and the compute machines.
See the User-provisioned DNS requirements section for more information about the OpenShift Container Platform DNS requirements.
Validate your DNS configuration.
From your installation node, run DNS lookups against the record names of the Kubernetes API, the wildcard routes, and the cluster nodes. Validate that the IP addresses in the responses correspond to the correct components.
From your installation node, run reverse DNS lookups against the IP addresses of the load balancer and the cluster nodes. Validate that the record names in the responses correspond to the correct components.
See the Validating DNS resolution for user-provisioned infrastructure section for detailed DNS validation steps.
Provision the required API and application ingress load balancing infrastructure. See the Load balancing requirements for user-provisioned infrastructure section for more information about the requirements.
Some load balancing solutions require the DNS name resolution for the cluster nodes to be in place before the load balancing is initialized. |
You can validate your DNS configuration before installing OpenShift Container Platform on user-provisioned infrastructure.
The validation steps detailed in this section must succeed before you install your cluster. |
You have configured the required DNS records for your user-provisioned infrastructure.
From your installation node, run DNS lookups against the record names of the Kubernetes API, the wildcard routes, and the cluster nodes. Validate that the IP addresses contained in the responses correspond to the correct components.
Perform a lookup against the Kubernetes API record name. Check that the result points to the IP address of the API load balancer:
$ dig +noall +answer @<nameserver_ip> api.<cluster_name>.<base_domain> (1)
1 | Replace <nameserver_ip> with the IP address of the nameserver, <cluster_name> with your cluster name, and <base_domain> with your base domain name. |
api.ocp4.example.com. 604800 IN A 192.168.1.5
Perform a lookup against the Kubernetes internal API record name. Check that the result points to the IP address of the API load balancer:
$ dig +noall +answer @<nameserver_ip> api-int.<cluster_name>.<base_domain>
api-int.ocp4.example.com. 604800 IN A 192.168.1.5
Test an example *.apps.<cluster_name>.<base_domain>
DNS wildcard lookup. All of the application wildcard lookups must resolve to the IP address of the application ingress load balancer:
$ dig +noall +answer @<nameserver_ip> random.apps.<cluster_name>.<base_domain>
random.apps.ocp4.example.com. 604800 IN A 192.168.1.5
In the example outputs, the same load balancer is used for the Kubernetes API and application ingress traffic. In production scenarios, you can deploy the API and application ingress load balancers separately so that you can scale the load balancer infrastructure for each in isolation. |
You can replace random
with another wildcard value. For example, you can query the route to the OpenShift Container Platform console:
$ dig +noall +answer @<nameserver_ip> console-openshift-console.apps.<cluster_name>.<base_domain>
console-openshift-console.apps.ocp4.example.com. 604800 IN A 192.168.1.5
Run a lookup against the bootstrap DNS record name. Check that the result points to the IP address of the bootstrap node:
$ dig +noall +answer @<nameserver_ip> bootstrap.<cluster_name>.<base_domain>
bootstrap.ocp4.example.com. 604800 IN A 192.168.1.96
Use this method to perform lookups against the DNS record names for the control plane and compute nodes. Check that the results correspond to the IP addresses of each node.
From your installation node, run reverse DNS lookups against the IP addresses of the load balancer and the cluster nodes. Validate that the record names contained in the responses correspond to the correct components.
Perform a reverse lookup against the IP address of the API load balancer. Check that the response includes the record names for the Kubernetes API and the Kubernetes internal API:
$ dig +noall +answer @<nameserver_ip> -x 192.168.1.5
5.1.168.192.in-addr.arpa. 604800 IN PTR api-int.ocp4.example.com. (1)
5.1.168.192.in-addr.arpa. 604800 IN PTR api.ocp4.example.com. (2)
1 | Provides the record name for the Kubernetes internal API. |
2 | Provides the record name for the Kubernetes API. |
A PTR record is not required for the OpenShift Container Platform application wildcard. No validation step is needed for reverse DNS resolution against the IP address of the application ingress load balancer. |
Perform a reverse lookup against the IP address of the bootstrap node. Check that the result points to the DNS record name of the bootstrap node:
$ dig +noall +answer @<nameserver_ip> -x 192.168.1.96
96.1.168.192.in-addr.arpa. 604800 IN PTR bootstrap.ocp4.example.com.
Use this method to perform reverse lookups against the IP addresses for the control plane and compute nodes. Check that the results correspond to the DNS record names of each node.
During an OpenShift Container Platform installation, you can provide an SSH public key to the installation program. The key is passed to the Red Hat Enterprise Linux CoreOS (RHCOS) nodes through their Ignition config files and is used to authenticate SSH access to the nodes. The key is added to the ~/.ssh/authorized_keys
list for the core
user on each node, which enables password-less authentication.
After the key is passed to the nodes, you can use the key pair to SSH in to the RHCOS nodes as the user core
. To access the nodes through SSH, the private key identity must be managed by SSH for your local user.
If you want to SSH in to your cluster nodes to perform installation debugging or disaster recovery, you must provide the SSH public key during the installation process. The ./openshift-install gather
command also requires the SSH public key to be in place on the cluster nodes.
Do not skip this procedure in production environments, where disaster recovery and debugging is required. |
If you do not have an existing SSH key pair on your local machine to use for authentication onto your cluster nodes, create one. For example, on a computer that uses a Linux operating system, run the following command:
$ ssh-keygen -t ed25519 -N '' -f <path>/<file_name> (1)
1 | Specify the path and file name, such as ~/.ssh/id_ed25519 , of the new SSH key. If you have an existing key pair, ensure your public key is in the your ~/.ssh directory. |
If you plan to install an OpenShift Container Platform cluster that uses the RHEL cryptographic libraries that have been submitted to NIST for FIPS 140-2/140-3 Validation on only the |
View the public SSH key:
$ cat <path>/<file_name>.pub
For example, run the following to view the ~/.ssh/id_ed25519.pub
public key:
$ cat ~/.ssh/id_ed25519.pub
Add the SSH private key identity to the SSH agent for your local user, if it has not already been added. SSH agent management of the key is required for password-less SSH authentication onto your cluster nodes, or if you want to use the ./openshift-install gather
command.
On some distributions, default SSH private key identities such as |
If the ssh-agent
process is not already running for your local user, start it as a background task:
$ eval "$(ssh-agent -s)"
Agent pid 31874
If your cluster is in FIPS mode, only use FIPS-compliant algorithms to generate the SSH key. The key must be either RSA or ECDSA. |
Add your SSH private key to the ssh-agent
:
$ ssh-add <path>/<file_name> (1)
1 | Specify the path and file name for your SSH private key, such as ~/.ssh/id_ed25519 |
Identity added: /home/<you>/<path>/<file_name> (<computer_name>)
When you install OpenShift Container Platform, provide the SSH public key to the installation program.
Before you install OpenShift Container Platform, download the installation file on your provisioning machine.
You have a machine that runs Linux, for example Red Hat Enterprise Linux (RHEL) 8, with at least 1.2 GB of local disk space.
Go to the Cluster Type page on the Red Hat Hybrid Cloud Console. If you have a Red Hat account, log in with your credentials. If you do not, create an account.
Select your infrastructure provider from the Run it yourself section of the page.
Select your host operating system and architecture from the dropdown menus under OpenShift Installer and click Download Installer.
Place the downloaded file in the directory where you want to store the installation configuration files.
|
Extract the installation program. For example, on a computer that uses a Linux operating system, run the following command:
$ tar -xvf openshift-install-linux.tar.gz
Download your installation pull secret from Red Hat OpenShift Cluster Manager. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OpenShift Container Platform components.
Alternatively, you can retrieve the installation program from the Red Hat Customer Portal, where you can specify a version of the installation program to download. However, you must have an active subscription to access this page. |
You can install the OpenShift CLI (oc
) to interact with
OpenShift Container Platform
from a command-line interface. You can install oc
on Linux, Windows, or macOS.
If you installed an earlier version of |
You can install the OpenShift CLI (oc
) binary on Linux by using the following procedure.
Navigate to the OpenShift Container Platform downloads page on the Red Hat Customer Portal.
Select the architecture from the Product Variant drop-down list.
Select the appropriate version from the Version drop-down list.
Click Download Now next to the OpenShift v4.15 Linux Client entry and save the file.
Unpack the archive:
$ tar xvf <file>
Place the oc
binary in a directory that is on your PATH
.
To check your PATH
, execute the following command:
$ echo $PATH
After you install the OpenShift CLI, it is available using the oc
command:
$ oc <command>
You can install the OpenShift CLI (oc
) binary on Windows by using the following procedure.
Navigate to the OpenShift Container Platform downloads page on the Red Hat Customer Portal.
Select the appropriate version from the Version drop-down list.
Click Download Now next to the OpenShift v4.15 Windows Client entry and save the file.
Unzip the archive with a ZIP program.
Move the oc
binary to a directory that is on your PATH
.
To check your PATH
, open the command prompt and execute the following command:
C:\> path
After you install the OpenShift CLI, it is available using the oc
command:
C:\> oc <command>
You can install the OpenShift CLI (oc
) binary on macOS by using the following procedure.
Navigate to the OpenShift Container Platform downloads page on the Red Hat Customer Portal.
Select the appropriate version from the Version drop-down list.
Click Download Now next to the OpenShift v4.15 macOS Client entry and save the file.
For macOS arm64, choose the OpenShift v4.15 macOS arm64 Client entry. |
Unpack and unzip the archive.
Move the oc
binary to a directory on your PATH.
To check your PATH
, open a terminal and execute the following command:
$ echo $PATH
Verify your installation by using an oc
command:
$ oc <command>
Installing the cluster requires that you manually create the installation configuration file.
You have an SSH public key on your local machine to provide to the installation program. The key will be used for SSH authentication onto your cluster nodes for debugging and disaster recovery.
You have obtained the OpenShift Container Platform installation program and the pull secret for your cluster.
Create an installation directory to store your required installation assets in:
$ mkdir <installation_directory>
You must create a directory. Some installation assets, like bootstrap X.509 certificates have short expiration intervals, so you must not reuse an installation directory. If you want to reuse individual files from another cluster installation, you can copy them into your directory. However, the file names for the installation assets might change between releases. Use caution when copying installation files from an earlier OpenShift Container Platform version. |
Customize the sample install-config.yaml
file template that is provided and save
it in the <installation_directory>
.
You must name this configuration file |
Back up the install-config.yaml
file so that you can use it to install multiple clusters.
The |
You can customize the install-config.yaml
file to specify more details about your OpenShift Container Platform cluster’s platform or modify the values of the required parameters.
apiVersion: v1
baseDomain: example.com (1)
compute: (2)
- hyperthreading: Enabled (3)
name: worker
replicas: 0 (4)
architecture: s390x
controlPlane: (2)
hyperthreading: Enabled (3)
name: master
replicas: 3 (5)
architecture: s390x
metadata:
name: test (6)
networking:
clusterNetwork:
- cidr: 10.128.0.0/14 (7)
hostPrefix: 23 (8)
networkType: OVNKubernetes (9)
serviceNetwork: (10)
- 172.30.0.0/16
platform:
none: {} (11)
fips: false (12)
pullSecret: '{"auths": ...}' (13)
sshKey: 'ssh-ed25519 AAAA...' (14)
1 | The base domain of the cluster. All DNS records must be sub-domains of this base and include the cluster name. | ||||
2 | The controlPlane section is a single mapping, but the compute section is a sequence of mappings. To meet the requirements of the different data structures, the first line of the compute section must begin with a hyphen, - , and the first line of the controlPlane section must not. Only one control plane pool is used. |
||||
3 | Specifies whether to enable or disable simultaneous multithreading (SMT), or hyperthreading. By default, SMT is enabled to increase the performance of the cores in your machines. You can disable it by setting the parameter value to Disabled . If you disable SMT, you must disable it in all cluster machines; this includes both control plane and compute machines.
|
||||
4 | You must set this value to 0 when you install OpenShift Container Platform on user-provisioned infrastructure. In installer-provisioned installations, the parameter controls the number of compute machines that the cluster creates and manages for you. In user-provisioned installations, you must manually deploy the compute machines before you finish installing the cluster.
|
||||
5 | The number of control plane machines that you add to the cluster. Because the cluster uses these values as the number of etcd endpoints in the cluster, the value must match the number of control plane machines that you deploy. | ||||
6 | The cluster name that you specified in your DNS records. | ||||
7 | A block of IP addresses from which pod IP addresses are allocated. This block must not overlap with existing physical networks. These IP addresses are used for the pod network. If you need to access the pods from an external network, you must configure load balancers and routers to manage the traffic.
|
||||
8 | The subnet prefix length to assign to each individual node. For example, if hostPrefix is set to 23 , then each node is assigned a /23 subnet out of the given cidr , which allows for 510 (2^(32 - 23) - 2) pod IP addresses. If you are required to provide access to nodes from an external network, configure load balancers and routers to manage the traffic. |
||||
9 | The cluster network plugin to install. The default value OVNKubernetes is the only supported value. |
||||
10 | The IP address pool to use for service IP addresses. You can enter only one IP address pool. This block must not overlap with existing physical networks. If you need to access the services from an external network, configure load balancers and routers to manage the traffic. | ||||
11 | You must set the platform to none . You cannot provide additional platform configuration variables for
IBM Z® infrastructure.
|
||||
12 | Whether to enable or disable FIPS mode. By default, FIPS mode is not enabled. If FIPS mode is enabled, the Red Hat Enterprise Linux CoreOS (RHCOS) machines that OpenShift Container Platform runs on bypass the default Kubernetes cryptography suite and use the cryptography modules that are provided with RHCOS instead.
|
||||
13 | The pull secret from Red Hat OpenShift Cluster Manager. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OpenShift Container Platform components. | ||||
14 | The SSH public key for the core user in Red Hat Enterprise Linux CoreOS (RHCOS).
|
Production environments can deny direct access to the internet and instead have
an HTTP or HTTPS proxy available. You can configure a new OpenShift Container Platform
cluster to use a proxy by configuring the proxy settings in the
install-config.yaml
file.
You have an existing install-config.yaml
file.
You reviewed the sites that your cluster requires access to and determined whether any of them need to bypass the proxy. By default, all cluster egress traffic is proxied, including calls to hosting cloud provider APIs. You added sites to the Proxy
object’s spec.noProxy
field to bypass the proxy if necessary.
The For installations on Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, and Red Hat OpenStack Platform (RHOSP), the |
Edit your install-config.yaml
file and add the proxy settings. For example:
apiVersion: v1
baseDomain: my.domain.com
proxy:
httpProxy: http://<username>:<pswd>@<ip>:<port> (1)
httpsProxy: https://<username>:<pswd>@<ip>:<port> (2)
noProxy: example.com (3)
additionalTrustBundle: | (4)
-----BEGIN CERTIFICATE-----
<MY_TRUSTED_CA_CERT>
-----END CERTIFICATE-----
additionalTrustBundlePolicy: <policy_to_add_additionalTrustBundle> (5)
1 | A proxy URL to use for creating HTTP connections outside the cluster. The
URL scheme must be http . |
2 | A proxy URL to use for creating HTTPS connections outside the cluster. |
3 | A comma-separated list of destination domain names, IP addresses, or other network CIDRs to exclude from proxying. Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com , but not y.com . Use * to bypass the proxy for all destinations. |
4 | If provided, the installation program generates a config map that is named user-ca-bundle in
the openshift-config namespace that contains one or more additional CA
certificates that are required for proxying HTTPS connections. The Cluster Network
Operator then creates a trusted-ca-bundle config map that merges these contents
with the Red Hat Enterprise Linux CoreOS (RHCOS) trust bundle, and this config map is referenced in the trustedCA field of the Proxy object. The additionalTrustBundle field is required unless
the proxy’s identity certificate is signed by an authority from the RHCOS trust
bundle. |
5 | Optional: The policy to determine the configuration of the Proxy object to reference the user-ca-bundle config map in the trustedCA field. The allowed values are Proxyonly and Always . Use Proxyonly to reference the user-ca-bundle config map only when http/https proxy is configured. Use Always to always reference the user-ca-bundle config map. The default value is Proxyonly . |
The installation program does not support the proxy |
If the installer times out, restart and then complete the deployment by using the
|
Save the file and reference it when installing OpenShift Container Platform.
The installation program creates a cluster-wide proxy that is named cluster
that uses the proxy
settings in the provided install-config.yaml
file. If no proxy settings are
provided, a cluster
Proxy
object is still created, but it will have a nil
spec
.
Only the |
Optionally, you can deploy zero compute machines in a minimal three node cluster that consists of three control plane machines only. This provides smaller, more resource efficient clusters for cluster administrators and developers to use for testing, development, and production.
In three-node OpenShift Container Platform environments, the three control plane machines are schedulable, which means that your application workloads are scheduled to run on them.
You have an existing install-config.yaml
file.
Ensure that the number of compute replicas is set to 0
in your install-config.yaml
file, as shown in the following compute
stanza:
compute:
- name: worker
platform: {}
replicas: 0
You must set the value of the |
The preferred resource for control plane nodes is six vCPUs and 21 GB. For three control plane nodes this is the memory + vCPU equivalent of a minimum five-node cluster. You should back the three nodes, each installed on a 120 GB disk, with three IFLs that are SMT2 enabled. The minimum tested setup is three vCPUs and 10 GB on a 120 GB disk for each control plane node. |
For three-node cluster installations, follow these next steps:
If you are deploying a three-node cluster with zero compute nodes, the Ingress Controller pods run on the control plane nodes. In three-node cluster deployments, you must configure your application ingress load balancer to route HTTP and HTTPS traffic to the control plane nodes. See the Load balancing requirements for user-provisioned infrastructure section for more information.
When you create the Kubernetes manifest files in the following procedure, ensure that the mastersSchedulable
parameter in the <installation_directory>/manifests/cluster-scheduler-02-config.yml
file is set to true
. This enables your application workloads to run on the control plane nodes.
Do not deploy any compute nodes when you create the Red Hat Enterprise Linux CoreOS (RHCOS) machines.
The configuration for the cluster network is specified as part of the Cluster Network Operator (CNO) configuration and stored in a custom resource (CR) object that is named cluster
. The CR specifies the fields for the Network
API in the operator.openshift.io
API group.
The CNO configuration inherits the following fields during cluster installation from the Network
API in the Network.config.openshift.io
API group:
clusterNetwork
IP address pools from which pod IP addresses are allocated.
serviceNetwork
IP address pool for services.
defaultNetwork.type
Cluster network plugin. OVNKubernetes
is the only supported plugin during installation.
You can specify the cluster network plugin configuration for your cluster by setting the fields for the defaultNetwork
object in the CNO object named cluster
.
The fields for the Cluster Network Operator (CNO) are described in the following table:
Field | Type | Description |
---|---|---|
|
|
The name of the CNO object. This name is always |
|
|
A list specifying the blocks of IP addresses from which pod IP addresses are allocated and the subnet prefix length assigned to each individual node in the cluster. For example:
|
|
|
A block of IP addresses for services. The OpenShift SDN and OVN-Kubernetes network plugins support only a single IP address block for the service network. For example:
You can customize this field only in the |
|
|
Configures the network plugin for the cluster network. |
|
|
The fields for this object specify the kube-proxy configuration. If you are using the OVN-Kubernetes cluster network plugin, the kube-proxy configuration has no effect. |
The values for the defaultNetwork
object are defined in the following table:
Field | Type | Description | ||
---|---|---|---|---|
|
|
|
||
|
|
This object is only valid for the OVN-Kubernetes network plugin. |
The following table describes the configuration fields for the OVN-Kubernetes network plugin:
Field | Type | Description | ||
---|---|---|---|---|
|
|
The maximum transmission unit (MTU) for the Geneve (Generic Network Virtualization Encapsulation) overlay network. This is detected automatically based on the MTU of the primary network interface. You do not normally need to override the detected MTU. If the auto-detected value is not what you expect it to be, confirm that the MTU on the primary network interface on your nodes is correct. You cannot use this option to change the MTU value of the primary network interface on the nodes. If your cluster requires different MTU values for different nodes, you must set this value to |
||
|
|
The port to use for all Geneve packets. The default value is |
||
|
|
Specify a configuration object for customizing the IPsec configuration. |
||
|
|
Specify a configuration object for customizing network policy audit logging. If unset, the defaults audit log settings are used. |
||
|
|
Optional: Specify a configuration object for customizing how egress traffic is sent to the node gateway.
|
||
|
If your existing network infrastructure overlaps with the This field cannot be changed after installation. |
The default value is |
||
|
If your existing network infrastructure overlaps with the This field cannot be changed after installation. |
The default value is |
Field | Type | Description |
---|---|---|
|
integer |
The maximum number of messages to generate every second per node. The default value is |
|
integer |
The maximum size for the audit log in bytes. The default value is |
|
integer |
The maximum number of log files that are retained. |
|
string |
One of the following additional audit log targets:
|
|
string |
The syslog facility, such as |
Field | Type | Description |
---|---|---|
|
|
Set this field to This field has an interaction with the Open vSwitch hardware offloading feature.
If you set this field to |
|
|
You can control IP forwarding for all traffic on OVN-Kubernetes managed interfaces by using the |
Field | Type | Description |
---|---|---|
|
|
Specifies the behavior of the IPsec implementation. Must be one of the following values:
|
defaultNetwork:
type: OVNKubernetes
ovnKubernetesConfig:
mtu: 1400
genevePort: 6081
ipsecConfig:
mode: Full
Using OVNKubernetes can lead to a stack exhaustion problem on IBM Power®. |
The values for the kubeProxyConfig
object are defined in the following table:
Field | Type | Description | ||
---|---|---|---|---|
|
|
The refresh period for
|
||
|
|
The minimum duration before refreshing
|
Because you must modify some cluster definition files and manually start the cluster machines, you must generate the Kubernetes manifest and Ignition config files that the cluster needs to configure the machines.
The installation configuration file transforms into the Kubernetes manifests. The manifests wrap into the Ignition configuration files, which are later used to configure the cluster machines.
|
The installation program that generates the manifest and Ignition files is architecture specific and can be obtained from the client image mirror. The Linux version of the installation program runs on s390x only. This installer program is also available as a Mac OS version. |
You obtained the OpenShift Container Platform installation program.
You created the install-config.yaml
installation configuration file.
Change to the directory that contains the OpenShift Container Platform installation program and generate the Kubernetes manifests for the cluster:
$ ./openshift-install create manifests --dir <installation_directory> (1)
1 | For <installation_directory> , specify the installation directory that
contains the install-config.yaml file you created. |
If you are installing a three-node cluster, skip the following step to allow the control plane nodes to be schedulable. |
When you configure control plane nodes from the default unschedulable to schedulable, additional subscriptions are required. This is because control plane nodes then become compute nodes. |
Check that the mastersSchedulable
parameter in the <installation_directory>/manifests/cluster-scheduler-02-config.yml
Kubernetes manifest file is set to false
. This setting prevents pods from being scheduled on the control plane machines:
Open the <installation_directory>/manifests/cluster-scheduler-02-config.yml
file.
Locate the mastersSchedulable
parameter and ensure that it is set to false
.
Save and exit the file.
To create the Ignition configuration files, run the following command from the directory that contains the installation program:
$ ./openshift-install create ignition-configs --dir <installation_directory> (1)
1 | For <installation_directory> , specify the same installation directory. |
Ignition config files are created for the bootstrap, control plane, and compute nodes in the installation directory. The kubeadmin-password
and kubeconfig
files are created in the ./<installation_directory>/auth
directory:
. ├── auth │ ├── kubeadmin-password │ └── kubeconfig ├── bootstrap.ign ├── master.ign ├── metadata.json └── worker.ign
Enabling NBDE disk encryption in an IBM Z® or IBM® LinuxONE environment requires additional steps, which are described in detail in this section.
You have set up the External Tang Server. See Network-bound disk encryption for instructions.
You have installed the butane
utility.
You have reviewed the instructions for how to create machine configs with Butane.
Create Butane configuration files for the control plane and compute nodes.
The following example of a Butane configuration for a control plane node creates a file named master-storage.bu
for disk encryption:
variant: openshift
version: 4.15.0
metadata:
name: master-storage
labels:
machineconfiguration.openshift.io/role: master
storage:
luks:
- clevis:
tang:
- thumbprint: QcPr_NHFJammnRCA3fFMVdNBwjs
url: http://clevis.example.com:7500
options: (1)
- --cipher
- aes-cbc-essiv:sha256
device: /dev/disk/by-partlabel/root (2)
label: luks-root
name: root
wipe_volume: true
filesystems:
- device: /dev/mapper/root
format: xfs
label: root
wipe_filesystem: true
openshift:
fips: true (3)
1 | The cipher option is only required if FIPS mode is enabled. Omit the entry if FIPS is disabled. |
2 | For installations on DASD-type disks, replace with device: /dev/disk/by-label/root . |
3 | Whether to enable or disable FIPS mode. By default, FIPS mode is not enabled. If FIPS mode is enabled, the Red Hat Enterprise Linux CoreOS (RHCOS) machines that OpenShift Container Platform runs on bypass the default Kubernetes cryptography suite and use the cryptography modules that are provided with RHCOS instead. |
Create a customized initramfs file to boot the machine, by running the following command:
$ coreos-installer pxe customize \
/root/rhcos-bootfiles/rhcos-<release>-live-initramfs.s390x.img \
--dest-device /dev/disk/by-id/scsi-<serial_number> --dest-karg-append \
ip=<ip_address>::<gateway_ip>:<subnet_mask>::<network_device>:none \
--dest-karg-append nameserver=<nameserver_ip> \
--dest-karg-append rd.neednet=1 -o \
/root/rhcos-bootfiles/<node_name>-initramfs.s390x.img
Before first boot, you must customize the initramfs for each node in the cluster, and add PXE kernel parameters. |
Create a parameter file that includes ignition.platform.id=metal
and ignition.firstboot
.
rd.neednet=1 \
console=ttysclp0 \
coreos.inst.install_dev=/dev/dasda \(1)
ignition.firstboot ignition.platform.id=metal \
coreos.live.rootfs_url=http://<http_server>/rhcos-<version>-live-rootfs.<architecture>.img \(2)
coreos.inst.ignition_url=http://<http_server>/master.ign \(3)
ip=10.19.17.2::10.19.17.1:255.255.255.0::enbdd0:none nameserver=10.19.17.1 \
zfcp.allow_lun_scan=0 \(4)
rd.znet=qeth,0.0.bdd0,0.0.bdd1,0.0.bdd2,layer2=1 \
rd.zfcp=0.0.5677,0x600606680g7f0056,0x034F000000000000 \(5)
1 | For installations on DASD-type disks, add coreos.inst.install_dev=/dev/dasda . Omit this value for FCP-type disks. |
2 | Specify the location of the rootfs artifact for the kernel and initramfs you are booting. Only HTTP and HTTPS protocols are supported. |
3 | Specify the location of the Ignition config file. Use master.ign or worker.ign . Only HTTP and HTTPS protocols are supported. |
4 | For installations on FCP-type disks, add zfcp.allow_lun_scan=0 . Omit this value for DASD-type disks. |
5 | For installations on DASD-type disks, replace with rd.dasd=0.0.3490 to specify the DASD device. |
Write all options in the parameter file as a single line and make sure you have no newline characters. |
To install OpenShift Container Platform on IBM Z® infrastructure that you provision, you must install Red Hat Enterprise Linux CoreOS (RHCOS) on z/VM guest virtual machines. When you install RHCOS, you must provide the Ignition config file that was generated by the OpenShift Container Platform installation program for the type of machine you are installing. If you have configured suitable networking, DNS, and load balancing infrastructure, the OpenShift Container Platform bootstrap process begins automatically after the RHCOS z/VM guest virtual machines have rebooted.
Complete the following steps to create the machines.
An HTTP or HTTPS server running on your provisioning machine that is accessible to the machines you create.
Log in to Linux on your provisioning machine.
Obtain the Red Hat Enterprise Linux CoreOS (RHCOS) kernel, initramfs, and rootfs files from the RHCOS image mirror.
The RHCOS images might not change with every release of OpenShift Container Platform. You must download images with the highest version that is less than or equal to the OpenShift Container Platform version that you install. Only use the appropriate kernel, initramfs, and rootfs artifacts described in the following procedure. |
The file names contain the OpenShift Container Platform version number. They resemble the following examples:
kernel: rhcos-<version>-live-kernel-<architecture>
initramfs: rhcos-<version>-live-initramfs.<architecture>.img
rootfs: rhcos-<version>-live-rootfs.<architecture>.img
The rootfs image is the same for FCP and DASD. |
Create parameter files. The following parameters are specific for a particular virtual machine:
For ip=
, specify the following seven entries:
The IP address for the machine.
An empty string.
The gateway.
The netmask.
The machine host and domain name in the form hostname.domainname
. Omit this value to let RHCOS decide.
The network interface name. Omit this value to let RHCOS decide.
If you use static IP addresses, specify none
.
For coreos.inst.ignition_url=
, specify the Ignition file for the machine role. Use bootstrap.ign
, master.ign
, or worker.ign
. Only HTTP and HTTPS protocols are supported.
For coreos.live.rootfs_url=
, specify the matching rootfs artifact for the kernel and initramfs you are booting. Only HTTP and HTTPS protocols are supported.
For installations on DASD-type disks, complete the following tasks:
For coreos.inst.install_dev=
, specify /dev/dasda
.
Use rd.dasd=
to specify the DASD where RHCOS is to be installed.
Leave all other parameters unchanged.
Example parameter file, bootstrap-0.parm
, for the bootstrap machine:
rd.neednet=1 \
console=ttysclp0 \
coreos.inst.install_dev=/dev/dasda \
coreos.live.rootfs_url=http://cl1.provide.example.com:8080/assets/rhcos-live-rootfs.s390x.img \
coreos.inst.ignition_url=http://cl1.provide.example.com:8080/ignition/bootstrap.ign \
ip=172.18.78.2::172.18.78.1:255.255.255.0:::none nameserver=172.18.78.1 \
rd.znet=qeth,0.0.bdf0,0.0.bdf1,0.0.bdf2,layer2=1,portno=0 \
zfcp.allow_lun_scan=0 \
rd.dasd=0.0.3490
Write all options in the parameter file as a single line and make sure you have no newline characters.
For installations on FCP-type disks, complete the following tasks:
Use rd.zfcp=<adapter>,<wwpn>,<lun>
to specify the FCP disk where RHCOS is to be installed. For multipathing repeat this step for each additional path.
When you install with multiple paths, you must enable multipathing directly after the installation, not at a later point in time, as this can cause problems. |
Set the install device as: coreos.inst.install_dev=/dev/disk/by-id/scsi-<serial_number>
.
If additional LUNs are configured with NPIV, FCP requires |
Leave all other parameters unchanged.
Additional postinstallation steps are required to fully enable multipathing. For more information, see “Enabling multipathing with kernel arguments on RHCOS" in Postinstallation machine configuration tasks. |
The following is an example parameter file worker-1.parm
for a worker node with multipathing:
rd.neednet=1 \
console=ttysclp0 \
coreos.inst.install_dev=/dev/disk/by-id/scsi-<serial_number> \
coreos.live.rootfs_url=http://cl1.provide.example.com:8080/assets/rhcos-live-rootfs.s390x.img \
coreos.inst.ignition_url=http://cl1.provide.example.com:8080/ignition/worker.ign \
ip=172.18.78.2::172.18.78.1:255.255.255.0:::none nameserver=172.18.78.1 \
rd.znet=qeth,0.0.bdf0,0.0.bdf1,0.0.bdf2,layer2=1,portno=0 \
zfcp.allow_lun_scan=0 \
rd.zfcp=0.0.1987,0x50050763070bc5e3,0x4008400B00000000 \
rd.zfcp=0.0.19C7,0x50050763070bc5e3,0x4008400B00000000 \
rd.zfcp=0.0.1987,0x50050763071bc5e3,0x4008400B00000000 \
rd.zfcp=0.0.19C7,0x50050763071bc5e3,0x4008400B00000000
Write all options in the parameter file as a single line and make sure you have no newline characters.
Transfer the initramfs, kernel, parameter files, and RHCOS images to z/VM, for example with FTP. For details about how to transfer the files with FTP and boot from the virtual reader, see Installing under Z/VM.
Punch the files to the virtual reader of the z/VM guest virtual machine that is to become your bootstrap node.
See PUNCH in IBM Documentation.
You can use the CP PUNCH command or, if you use Linux, the vmur command to transfer files between two z/VM guest virtual machines. |
Log in to CMS on the bootstrap machine.
IPL the bootstrap machine from the reader:
$ ipl c
See IPL in IBM Documentation.
Repeat this procedure for the other machines in the cluster.
This section illustrates the networking configuration and other advanced options that allow you to modify the Red Hat Enterprise Linux CoreOS (RHCOS) manual installation process. The following tables describe the kernel arguments and command-line options you can use with the RHCOS live installer and the coreos-installer
command.
If you install RHCOS from an ISO image, you can add kernel arguments manually when you boot the image to configure networking for a node. If no networking arguments are specified, DHCP is activated in the initramfs when RHCOS detects that networking is required to fetch the Ignition config file.
When adding networking arguments manually, you must also add the |
The following information provides examples for configuring networking and bonding on your RHCOS nodes for ISO installations. The examples describe how to use the ip=
, nameserver=
, and bond=
kernel arguments.
Ordering is important when adding the kernel arguments: |
The networking options are passed to the dracut
tool during system boot. For more information about the networking options supported by dracut
, see the dracut.cmdline
manual page.
The following examples are the networking options for ISO installation.
To configure an IP address, either use DHCP (ip=dhcp
) or set an individual static IP address (ip=<host_ip>
). If setting a static IP, you must then identify the DNS server IP address (nameserver=<dns_ip>
) on each node. The following example sets:
The node’s IP address to 10.10.10.2
The gateway address to 10.10.10.254
The netmask to 255.255.255.0
The hostname to core0.example.com
The DNS server address to 4.4.4.41
The auto-configuration value to none
. No auto-configuration is required when IP networking is configured statically.
ip=10.10.10.2::10.10.10.254:255.255.255.0:core0.example.com:enp1s0:none
nameserver=4.4.4.41
When you use DHCP to configure IP addressing for the RHCOS machines, the machines also obtain the DNS server information through DHCP. For DHCP-based deployments, you can define the DNS server address that is used by the RHCOS nodes through your DHCP server configuration. |
You can configure an IP address without assigning a static hostname. If a static hostname is not set by the user, it will be picked up and automatically set by a reverse DNS lookup. To configure an IP address without a static hostname refer to the following example:
The node’s IP address to 10.10.10.2
The gateway address to 10.10.10.254
The netmask to 255.255.255.0
The DNS server address to 4.4.4.41
The auto-configuration value to none
. No auto-configuration is required when IP networking is configured statically.
ip=10.10.10.2::10.10.10.254:255.255.255.0::enp1s0:none
nameserver=4.4.4.41
You can specify multiple network interfaces by setting multiple ip=
entries.
ip=10.10.10.2::10.10.10.254:255.255.255.0:core0.example.com:enp1s0:none
ip=10.10.10.3::10.10.10.254:255.255.255.0:core0.example.com:enp2s0:none
Optional: You can configure routes to additional networks by setting an rd.route=
value.
When you configure one or multiple networks, one default gateway is required. If the additional network gateway is different from the primary network gateway, the default gateway must be the primary network gateway. |
Run the following command to configure the default gateway:
ip=::10.10.10.254::::
Enter the following command to configure the route for the additional network:
rd.route=20.20.20.0/24:20.20.20.254:enp2s0
You can disable DHCP on a single interface, such as when there are two or more network interfaces and only one interface is being used. In the example, the enp1s0
interface has a static networking configuration and DHCP is disabled for enp2s0
, which is not used:
ip=10.10.10.2::10.10.10.254:255.255.255.0:core0.example.com:enp1s0:none
ip=::::core0.example.com:enp2s0:none
You can combine DHCP and static IP configurations on systems with multiple network interfaces, for example:
ip=enp1s0:dhcp
ip=10.10.10.2::10.10.10.254:255.255.255.0:core0.example.com:enp2s0:none
Optional: You can configure VLANs on individual interfaces by using the vlan=
parameter.
To configure a VLAN on a network interface and use a static IP address, run the following command:
ip=10.10.10.2::10.10.10.254:255.255.255.0:core0.example.com:enp2s0.100:none
vlan=enp2s0.100:enp2s0
To configure a VLAN on a network interface and to use DHCP, run the following command:
ip=enp2s0.100:dhcp
vlan=enp2s0.100:enp2s0
You can provide multiple DNS servers by adding a nameserver=
entry for each server, for example:
nameserver=1.1.1.1
nameserver=8.8.8.8
Optional: You can bond multiple network interfaces to a single interface by using the bond=
option. Refer to the following examples:
The syntax for configuring a bonded interface is: bond=<name>[:<network_interfaces>][:options]
<name>
is the bonding device name (bond0
), <network_interfaces>
represents a comma-separated list of physical (ethernet) interfaces (em1,em2
),
and options is a comma-separated list of bonding options. Enter modinfo bonding
to see available options.
When you create a bonded interface using bond=
, you must specify how the IP address is assigned and other
information for the bonded interface.
To configure the bonded interface to use DHCP, set the bond’s IP address to dhcp
. For example:
bond=bond0:em1,em2:mode=active-backup
ip=bond0:dhcp
To configure the bonded interface to use a static IP address, enter the specific IP address you want and related information. For example:
bond=bond0:em1,em2:mode=active-backup,fail_over_mac=1
ip=10.10.10.2::10.10.10.254:255.255.255.0:core0.example.com:bond0:none
Always set the fail_over_mac=1
option in active-backup mode, to avoid problems when shared OSA/RoCE cards are used.
Optional: You can configure VLANs on bonded interfaces by using the vlan=
parameter and to use DHCP, for example:
ip=bond0.100:dhcp
bond=bond0:em1,em2:mode=active-backup
vlan=bond0.100:bond0
Use the following example to configure the bonded interface with a VLAN and to use a static IP address:
ip=10.10.10.2::10.10.10.254:255.255.255.0:core0.example.com:bond0.100:none
bond=bond0:em1,em2:mode=active-backup
vlan=bond0.100:bond0
Optional: You can use a network teaming as an alternative to bonding by using the team=
parameter:
The syntax for configuring a team interface is: team=name[:network_interfaces]
name is the team device name (team0
) and network_interfaces represents a comma-separated list of physical (ethernet) interfaces (em1, em2
).
Teaming is planned to be deprecated when RHCOS switches to an upcoming version of RHEL. For more information, see this Red Hat Knowledgebase Article. |
Use the following example to configure a network team:
team=team0:em1,em2
ip=team0:dhcp
The OpenShift Container Platform bootstrap process begins after the cluster nodes first boot into the persistent RHCOS environment that has been installed to disk. The configuration information provided through the Ignition config files is used to initialize the bootstrap process and install OpenShift Container Platform on the machines. You must wait for the bootstrap process to complete.
You have created the Ignition config files for your cluster.
You have configured suitable network, DNS and load balancing infrastructure.
You have obtained the installation program and generated the Ignition config files for your cluster.
You installed RHCOS on your cluster machines and provided the Ignition config files that the OpenShift Container Platform installation program generated.
Your machines have direct internet access or have an HTTP or HTTPS proxy available.
Monitor the bootstrap process:
$ ./openshift-install --dir <installation_directory> wait-for bootstrap-complete \ (1)
--log-level=info (2)
1 | For <installation_directory> , specify the path to the directory that you stored the installation files in. |
2 | To view different installation details, specify warn , debug , or error instead of info . |
INFO Waiting up to 30m0s for the Kubernetes API at https://api.test.example.com:6443...
INFO API v1.28.5 up
INFO Waiting up to 30m0s for bootstrapping to complete...
INFO It is now safe to remove the bootstrap resources
The command succeeds when the Kubernetes API server signals that it has been bootstrapped on the control plane machines.
After the bootstrap process is complete, remove the bootstrap machine from the load balancer.
You must remove the bootstrap machine from the load balancer at this point. You can also remove or reformat the bootstrap machine itself. |
You can log in to your cluster as a default system user by exporting the cluster kubeconfig
file.
The kubeconfig
file contains information about the cluster that is used by the CLI to connect a client to the correct cluster and API server.
The file is specific to a cluster and is created during OpenShift Container Platform installation.
You deployed an OpenShift Container Platform cluster.
You installed the oc
CLI.
Export the kubeadmin
credentials:
$ export KUBECONFIG=<installation_directory>/auth/kubeconfig (1)
1 | For <installation_directory> , specify the path to the directory that you stored
the installation files in. |
Verify you can run oc
commands successfully using the exported configuration:
$ oc whoami
system:admin
When you add machines to a cluster, two pending certificate signing requests (CSRs) are generated for each machine that you added. You must confirm that these CSRs are approved or, if necessary, approve them yourself. The client requests must be approved first, followed by the server requests.
You added machines to your cluster.
Confirm that the cluster recognizes the machines:
$ oc get nodes
NAME STATUS ROLES AGE VERSION
master-0 Ready master 63m v1.28.5
master-1 Ready master 63m v1.28.5
master-2 Ready master 64m v1.28.5
The output lists all of the machines that you created.
The preceding output might not include the compute nodes, also known as worker nodes, until some CSRs are approved. |
Review the pending CSRs and ensure that you see the client requests with the Pending
or Approved
status for each machine that you added to the cluster:
$ oc get csr
NAME AGE REQUESTOR CONDITION
csr-mddf5 20m system:node:master-01.example.com Approved,Issued
csr-z5rln 16m system:node:worker-21.example.com Approved,Issued
If the CSRs were not approved, after all of the pending CSRs for the machines you added are in Pending
status, approve the CSRs for your cluster machines:
Because the CSRs rotate automatically, approve your CSRs within an hour of adding the machines to the cluster. If you do not approve them within an hour, the certificates will rotate, and more than two certificates will be present for each node. You must approve all of these certificates. After the client CSR is approved, the Kubelet creates a secondary CSR for the serving certificate, which requires manual approval. Then, subsequent serving certificate renewal requests are automatically approved by the |
For clusters running on platforms that are not machine API enabled, such as bare metal and other user-provisioned infrastructure, you must implement a method of automatically approving the kubelet serving certificate requests (CSRs). If a request is not approved, then the |
To approve them individually, run the following command for each valid CSR:
$ oc adm certificate approve <csr_name> (1)
1 | <csr_name> is the name of a CSR from the list of current CSRs. |
To approve all pending CSRs, run the following command:
$ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs --no-run-if-empty oc adm certificate approve
Some Operators might not become available until some CSRs are approved. |
Now that your client requests are approved, you must review the server requests for each machine that you added to the cluster:
$ oc get csr
NAME AGE REQUESTOR CONDITION
csr-bfd72 5m26s system:node:ip-10-0-50-126.us-east-2.compute.internal Pending
csr-c57lv 5m26s system:node:ip-10-0-95-157.us-east-2.compute.internal Pending
...
If the remaining CSRs are not approved, and are in the Pending
status, approve the CSRs for your cluster machines:
To approve them individually, run the following command for each valid CSR:
$ oc adm certificate approve <csr_name> (1)
1 | <csr_name> is the name of a CSR from the list of current CSRs. |
To approve all pending CSRs, run the following command:
$ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs oc adm certificate approve
After all client and server CSRs have been approved, the machines have the Ready
status. Verify this by running the following command:
$ oc get nodes
NAME STATUS ROLES AGE VERSION
master-0 Ready master 73m v1.28.5
master-1 Ready master 73m v1.28.5
master-2 Ready master 74m v1.28.5
worker-0 Ready worker 11m v1.28.5
worker-1 Ready worker 11m v1.28.5
It can take a few minutes after approval of the server CSRs for the machines to transition to the |
For more information on CSRs, see Certificate Signing Requests.
After the control plane initializes, you must immediately configure some Operators so that they all become available.
Your control plane has initialized.
Watch the cluster components come online:
$ watch -n5 oc get clusteroperators
NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE
authentication 4.15.0 True False False 19m
baremetal 4.15.0 True False False 37m
cloud-credential 4.15.0 True False False 40m
cluster-autoscaler 4.15.0 True False False 37m
config-operator 4.15.0 True False False 38m
console 4.15.0 True False False 26m
csi-snapshot-controller 4.15.0 True False False 37m
dns 4.15.0 True False False 37m
etcd 4.15.0 True False False 36m
image-registry 4.15.0 True False False 31m
ingress 4.15.0 True False False 30m
insights 4.15.0 True False False 31m
kube-apiserver 4.15.0 True False False 26m
kube-controller-manager 4.15.0 True False False 36m
kube-scheduler 4.15.0 True False False 36m
kube-storage-version-migrator 4.15.0 True False False 37m
machine-api 4.15.0 True False False 29m
machine-approver 4.15.0 True False False 37m
machine-config 4.15.0 True False False 36m
marketplace 4.15.0 True False False 37m
monitoring 4.15.0 True False False 29m
network 4.15.0 True False False 38m
node-tuning 4.15.0 True False False 37m
openshift-apiserver 4.15.0 True False False 32m
openshift-controller-manager 4.15.0 True False False 30m
openshift-samples 4.15.0 True False False 32m
operator-lifecycle-manager 4.15.0 True False False 37m
operator-lifecycle-manager-catalog 4.15.0 True False False 37m
operator-lifecycle-manager-packageserver 4.15.0 True False False 32m
service-ca 4.15.0 True False False 38m
storage 4.15.0 True False False 37m
Configure the Operators that are not available.
The Image Registry Operator is not initially available for platforms that do not provide default storage. After installation, you must configure your registry to use storage so that the Registry Operator is made available.
Instructions are shown for configuring a persistent volume, which is required for production clusters. Where applicable, instructions are shown for configuring an empty directory as the storage location, which is available for only non-production clusters.
Additional instructions are provided for allowing the image registry to use block storage types by using the Recreate
rollout strategy during upgrades.
As a cluster administrator, following installation you must configure your registry to use storage.
You have access to the cluster as a user with the cluster-admin
role.
You have a cluster on IBM Z®.
You have provisioned persistent storage for your cluster, such as Red Hat OpenShift Data Foundation.
OpenShift Container Platform supports |
Must have 100Gi capacity.
To configure your registry to use storage, change the spec.storage.pvc
in
the configs.imageregistry/cluster
resource.
When you use shared storage, review your security settings to prevent outside access. |
Verify that you do not have a registry pod:
$ oc get pod -n openshift-image-registry -l docker-registry=default
No resources found in openshift-image-registry namespace
If you do have a registry pod in your output, you do not need to continue with this procedure. |
Check the registry configuration:
$ oc edit configs.imageregistry.operator.openshift.io
storage:
pvc:
claim:
Leave the claim
field blank to allow the automatic creation of an
image-registry-storage
PVC.
Check the clusteroperator
status:
$ oc get clusteroperator image-registry
NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE MESSAGE
image-registry 4.15 True False False 6h50m
Ensure that your registry is set to managed to enable building and pushing of images.
Run:
$ oc edit configs.imageregistry/cluster
Then, change the line
managementState: Removed
to
managementState: Managed
You must configure storage for the Image Registry Operator. For non-production clusters, you can set the image registry to an empty directory. If you do so, all images are lost if you restart the registry.
To set the image registry storage to an empty directory:
$ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"storage":{"emptyDir":{}}}}'
Configure this option for only non-production clusters. |
If you run this command before the Image Registry Operator initializes its
components, the oc patch
command fails with the following error:
Error from server (NotFound): configs.imageregistry.operator.openshift.io "cluster" not found
Wait a few minutes and run the command again.
After you complete the Operator configuration, you can finish installing the cluster on infrastructure that you provide.
Your control plane has initialized.
You have completed the initial Operator configuration.
Confirm that all the cluster components are online with the following command:
$ watch -n5 oc get clusteroperators
NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE
authentication 4.15.0 True False False 19m
baremetal 4.15.0 True False False 37m
cloud-credential 4.15.0 True False False 40m
cluster-autoscaler 4.15.0 True False False 37m
config-operator 4.15.0 True False False 38m
console 4.15.0 True False False 26m
csi-snapshot-controller 4.15.0 True False False 37m
dns 4.15.0 True False False 37m
etcd 4.15.0 True False False 36m
image-registry 4.15.0 True False False 31m
ingress 4.15.0 True False False 30m
insights 4.15.0 True False False 31m
kube-apiserver 4.15.0 True False False 26m
kube-controller-manager 4.15.0 True False False 36m
kube-scheduler 4.15.0 True False False 36m
kube-storage-version-migrator 4.15.0 True False False 37m
machine-api 4.15.0 True False False 29m
machine-approver 4.15.0 True False False 37m
machine-config 4.15.0 True False False 36m
marketplace 4.15.0 True False False 37m
monitoring 4.15.0 True False False 29m
network 4.15.0 True False False 38m
node-tuning 4.15.0 True False False 37m
openshift-apiserver 4.15.0 True False False 32m
openshift-controller-manager 4.15.0 True False False 30m
openshift-samples 4.15.0 True False False 32m
operator-lifecycle-manager 4.15.0 True False False 37m
operator-lifecycle-manager-catalog 4.15.0 True False False 37m
operator-lifecycle-manager-packageserver 4.15.0 True False False 32m
service-ca 4.15.0 True False False 38m
storage 4.15.0 True False False 37m
Alternatively, the following command notifies you when all of the clusters are available. It also retrieves and displays credentials:
$ ./openshift-install --dir <installation_directory> wait-for install-complete (1)
1 | For <installation_directory> , specify the path to the directory that you
stored the installation files in. |
INFO Waiting up to 30m0s for the cluster to initialize...
The command succeeds when the Cluster Version Operator finishes deploying the OpenShift Container Platform cluster from Kubernetes API server.
|
Confirm that the Kubernetes API server is communicating with the pods.
To view a list of all pods, use the following command:
$ oc get pods --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
openshift-apiserver-operator openshift-apiserver-operator-85cb746d55-zqhs8 1/1 Running 1 9m
openshift-apiserver apiserver-67b9g 1/1 Running 0 3m
openshift-apiserver apiserver-ljcmx 1/1 Running 0 1m
openshift-apiserver apiserver-z25h4 1/1 Running 0 2m
openshift-authentication-operator authentication-operator-69d5d8bf84-vh2n8 1/1 Running 0 5m
...
View the logs for a pod that is listed in the output of the previous command by using the following command:
$ oc logs <pod_name> -n <namespace> (1)
1 | Specify the pod name and namespace, as shown in the output of the previous command. |
If the pod logs display, the Kubernetes API server can communicate with the cluster machines.
For an installation with Fibre Channel Protocol (FCP), additional steps are required to enable multipathing. Do not enable multipathing during installation.
See "Enabling multipathing with kernel arguments on RHCOS" in the Postinstallation machine configuration tasks documentation for more information.
In OpenShift Container Platform 4.15, the Telemetry service, which runs by default to provide metrics about cluster health and the success of updates, requires internet access. If your cluster is connected to the internet, Telemetry runs automatically, and your cluster is registered to OpenShift Cluster Manager.
After you confirm that your OpenShift Cluster Manager inventory is correct, either maintained automatically by Telemetry or manually by using OpenShift Cluster Manager, use subscription watch to track your OpenShift Container Platform subscriptions at the account or multi-cluster level.
See About remote health monitoring for more information about the Telemetry service
How to generate SOSREPORT within OpenShift4 nodes without SSH.
If necessary, you can opt out of remote health reporting.