Overview

An etcd performance issue has been discovered on new and upgraded OpenShift Container Platform 3.4 clusters. See the following Knowledgebase Solution for further details:

If you installed using the advanced installation and the inventory file that was used is available, you can use the upgrade playbook to automate the OpenShift cluster upgrade process. If you installed using the quick installation method and a ~/.config/openshift/installer.cfg.yml file is available, you can use the installer to perform the automated upgrade.

The automated upgrade performs the following steps for you:

  • Applies the latest configuration.

  • Upgrades master and etcd components and restarts services.

  • Upgrades node components and restarts services.

  • Applies the latest cluster policies.

  • Updates the default router if one exists.

  • Updates the default registry if one exists.

  • Updates default image streams and InstantApp templates.

Ensure that you have met all prerequisites before proceeding with an upgrade. Failure to do so can result in a failed upgrade.

Preparing for an Automated Upgrade

Before upgrading your cluster to OpenShift Container Platform 3.4, the cluster must be already upgraded to the latest asynchronous release of version 3.3. Cluster upgrades cannot span more than one minor version at a time, so if your cluster is at a version earlier than 3.3, you must first upgrade incrementally (e.g., 3.1 to 3.2, then 3.2 to 3.3).

Before attempting the upgrade, follow the steps in Verifying the Upgrade to verify the cluster’s health. This will confirm that nodes are in the Ready state, running the expected starting version, and will ensure that there are no diagnostic errors or warnings.

To prepare for an automated upgrade:

  1. If you are upgrading from OpenShift Container Platform 3.3 to 3.4, manually disable the 3.3 channel and enable the 3.4 channel on each master and node host:

    # subscription-manager repos --disable="rhel-7-server-ose-3.3-rpms" \
        --enable="rhel-7-server-ose-3.4-rpms"\
        --enable="rhel-7-server-extras-rpms"
    # yum clean all
  2. For any upgrade path, always ensure that you have the latest version of the atomic-openshift-utils package on each RHEL 7 system, which also updates the openshift-ansible-* packages:

    # yum update atomic-openshift-utils
  3. Install or update to the following latest available *-excluder packages on each RHEL 7 system, which helps ensure your systems stay on the correct versions of atomic-openshift and docker packages when you are not trying to upgrade, according to the OpenShift Container Platform version:

    # yum install atomic-openshift-excluder atomic-openshift-docker-excluder

    These packages add entries to the exclude directive in the host’s /etc/yum.conf file.

  4. You must be logged in as a cluster administrative user on the master host for the upgrade to succeed:

    $ oc login

After satisfying these steps, there are two methods for running the automated upgrade:

Choose and follow one of these methods.

Using the Installer to Upgrade

If you installed OpenShift Container Platform using the quick installation method, you should have an installation configuration file located at ~/.config/openshift/installer.cfg.yml. The installer requires this file to start an upgrade.

The installer supports upgrading between minor versions of OpenShift Container Platform (one minor version at a time, e.g., 3.3 to 3.4) as well as between asynchronous errata updates within a minor version (e.g., 3.4.z).

If you have an older format installation configuration file in ~/.config/openshift/installer.cfg.yml from an installation of a previous cluster version, the installer will attempt to upgrade the file to the new supported format. If you do not have an installation configuration file of any format, you can create one manually.

To start an upgrade with the quick installer:

  1. Satisfy the steps in Preparing for an Automated Upgrade to ensure you are using the latest upgrade playbooks.

  2. Run the following command on each host to remove the atomic-openshift packages from the list of yum excludes on the host:

    # atomic-openshift-excluder unexclude
  3. Run the installer with the upgrade subcommand:

    # atomic-openshift-installer upgrade
  4. Then, follow the on-screen instructions to upgrade to the latest release.

  5. Run the following command on each host to add the atomic-openshift packages back to the list of yum excludes on the host:

    # atomic-openshift-excluder exclude
  6. After all master and node upgrades have completed, a recommendation will be printed to reboot all hosts. After rebooting, if there are no additional features enabled, you can verify the upgrade. Otherwise, the next step depends on what additional features have you previously enabled.

    Feature Next Step

    Aggregated Logging

    Upgrade the EFK logging stack.

    Cluster Metrics

    Upgrade cluster metrics.

Running Upgrade Playbooks Directly

You can run automated upgrade playbooks using Ansible directly, similar to the advanced installation method, if you have an inventory file. Playbooks can be run using the ansible-playbook command.

The same v3_4 upgrade playbooks can be used for either of the following scenarios:

  • Upgrading existing OpenShift Container Platform 3.3 clusters to 3.4

  • Upgrading existing OpenShift Container Platform 3.4 clusters to the latest asynchronous errata updates

Upgrading the Control Plane and Nodes in Separate Phases

An OpenShift Container Platform cluster can be upgraded in one or more phases. You can choose whether to upgrade all hosts in one phase by running a single Ansible playbook, or upgrade the control plane (master components) and nodes in multiple phases using separate playbooks.

Instructions on the full upgrade process and when to call these playbooks are described in Upgrading to the Latest OpenShift Container Platform 3.4 Release.

When upgrading in separate phases, the control plane phase includes upgrading:

  • etcd

  • master components

  • Docker on any stand-alone etcd hosts

It does does not include:

  • node services running on masters

  • Docker running on masters

  • node services running on stand-alone nodes

When upgrading only the nodes, the control plane must already be upgraded. The node phase includes upgrading:

  • node services running on masters and stand-alone nodes

  • Docker running on masters and nodes

Customizing Node Upgrades

Whether upgrading in a single or multiple phases, you can customize how the node portion of the upgrade progresses by passing certain Ansible variables to an upgrade playbook using the -e option.

Instructions on the full upgrade process and when to call these playbooks are described in Upgrading to the Latest OpenShift Container Platform 3.4 Release.

The openshift_upgrade_nodes_serial variable can be set to an integer or percentage to control how many node hosts are upgraded at the same time. The default is 1, upgrading nodes one at a time.

For example, to upgrade 20 percent of the total number of detected nodes at a time:

$ ansible-playbook -i <path/to/inventory/file> \
    </path/to/upgrade/playbook> \
    -e openshift_upgrade_nodes_serial="20%"

The openshift_upgrade_nodes_label variable allows you to specify that only nodes with a certain label are upgraded. This can also be combined with the openshift_upgrade_nodes_serial variable.

For example, to only upgrade nodes in the group1 region, two at a time:

$ ansible-playbook -i <path/to/inventory/file> \
    </path/to/upgrade/playbook> \
    -e openshift_upgrade_nodes_serial="2" \
    -e openshift_upgrade_nodes_label="region=group1"

See Manging Nodes for more on node labels.

Upgrading to the Latest OpenShift Container Platform 3.4 Release

To upgrade an existing OpenShift Container Platform 3.3 or 3.4 cluster to the latest 3.4 release:

  1. Satisfy the steps in Preparing for an Automated Upgrade to ensure you are using the latest upgrade playbooks.

  2. Run the following command on each host to remove the atomic-openshift packages from the list of yum excludes on the host:

    # atomic-openshift-excluder unexclude
  3. Ensure the deployment_type parameter in your inventory file is set to openshift-enterprise.

  4. If you have multiple masters configured and want to enable rolling, full system restarts of the hosts, you can set the openshift_rolling_restart_mode parameter in your inventory file to system. Otherwise, the default value services performs rolling service restarts on HA masters, but does not reboot the systems. See Configuring Cluster Variables for details.

  5. At this point, you can choose to run the upgrade in a single or multiple phases. See Upgrading the Control Plane and Nodes in Separate Phases for more details which components are upgraded in each phase.

    If your inventory file is located somewhere other than the default /etc/ansible/hosts, add the -i flag to specify its location. If you previously used the atomic-openshift-installer command to run your installation, you can check ~/.config/openshift/hosts for the last inventory file that was used, if needed.

    You can add --tags pre_upgrade to the following ansible-playbook commands to run the pre-upgrade checks for the playbook. This is a dry-run option that preforms all pre-upgrade checks without actually upgrading any hosts, and reports any problems found.

    Option A) Upgrade control plane and nodes in a single phase.

    Run the upgrade.yml playbook to upgrade the cluster in a single phase using one playbook; the control plane is still upgraded first, then nodes in-place:

    # ansible-playbook -i </path/to/inventory/file> \
        /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-cluster/upgrades/v3_4/upgrade.yml \
        [-e <customized_node_upgrade_variables>] (1)
    1 See Customizing Node Upgrades for any desired <customized_node_upgrade_variables>.

    Option B) Upgrade the control plane and nodes in separate phases.

    1. To upgrade only the control plane, run the upgrade_control_plane.yaml playbook:

      # ansible-playbook -i </path/to/inventory/file> \
          /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-cluster/upgrades/v3_4/upgrade_control_plane.yml
    2. To upgrade only the nodes, run the upgrade_nodes.yaml playbook:

      # ansible-playbook -i </path/to/inventory/file> \
          /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-cluster/upgrades/v3_4/upgrade_nodes.yml \
          [-e <customized_node_upgrade_variables>] (1)
      1 See Customizing Node Upgrades for any desired <customized_node_upgrade_variables>.

      If you are upgrading the nodes in groups as described in Customizing Node Upgrades, continue invoking the upgrade_nodes.yml playbook until all nodes have been successfully upgraded.

  6. Run the following command on each host to add the atomic-openshift packages back to the list of yum excludes on the host:

    # atomic-openshift-excluder exclude
  7. After all master and node upgrades have completed, a recommendation will be printed to reboot all hosts. After rebooting, if there are no additional features enabled, you can verify the upgrade. Otherwise, the next step depends on what additional features have you previously enabled.

    Feature Next Step

    Aggregated Logging

    Upgrade the EFK logging stack.

    Cluster Metrics

    Upgrade cluster metrics.

Upgrading the EFK Logging Stack

If you have previously deployed the EFK logging stack and want to upgrade to the latest logging component images, the steps must be performed manually as shown in Manual Upgrades.

Upgrading Cluster Metrics

If you have previously deployed cluster metrics, you must manually update to the latest metric components.

Verifying the Upgrade

To verify the upgrade:

  1. First check that all nodes are marked as Ready:

    # oc get nodes
    NAME                        STATUS                     AGE
    master.example.com          Ready,SchedulingDisabled   165d
    node1.example.com           Ready                      165d
    node2.example.com           Ready                      165d
  2. Then, verify that you are running the expected versions of the docker-registry and router images, if deployed. Replace <tag> with v3.4.1.24 for the latest version.

    # oc get -n default dc/docker-registry -o json | grep \"image\"
        "image": "openshift3/ose-docker-registry:<tag>",
    # oc get -n default dc/router -o json | grep \"image\"
        "image": "openshift3/ose-haproxy-router:<tag>",
  3. You can use the diagnostics tool on the master to look for common issues:

    # oc adm diagnostics
    ...
    [Note] Summary of diagnostics execution:
    [Note] Completed with no errors or warnings seen.