Chapter 12. Upgrading the undercloud operating system

Procedure

1. Log in to the undercloud as the stack user.

2. Check the /etc/ssh/sshd_config file for the PermitRootLogin parameter:

   $ sudo grep PermitRootLogin /etc/ssh/sshd_config

3. If the parameter is not in the /etc/ssh/sshd_config file, edit the file and set the PermitRootLogin parameter:

   PermitRootLogin no

4. Save the file.

Procedure

1. Validate your SSH key size:

   ssh-keygen -l -f /home/stack/overcloud-deploy/overcloud/ssh_private_key

   Example output:

   1024 SHA256:Xqz0Xz0/aJua6B3qRD7VsLr6n/V3zhmnGSkcFR6FlJw stack@director.example.local (RSA)

2. If your SSH key is less than 2048 bits, you must rotate out the SSH key before continuing. For more information, see Updating SSH keys in your OpenStack environment in Hardening Red Hat OpenStack Platform.

Procedure

1. Log in to the undercloud as the stack user.

2. Create a file named system_upgrade.yaml in your templates directory and include the following content:

   parameter_defaults:
     UpgradeLeappDevelSkip: "LEAPP_UNSUPPORTED=1 LEAPP_DEVEL_SKIP_CHECK_OS_RELEASE=1 LEAPP_NO_NETWORK_RENAMING=1 LEAPP_DEVEL_TARGET_RELEASE=9.2 LEAPP_TARGET_PRODUCT_CHANNEL=e4s"
     UpgradeLeappDebug: false
     UpgradeLeappEnabled: true
     LeappActorsToRemove: ['checkifcfg','persistentnetnamesdisable','checkinstalledkernels','biosdevname']
     LeappRepoInitCommand: |
        subscription-manager repos --disable=*
        subscription-manager repos --enable rhel-8-for-x86_64-baseos-aus-rpms --enable rhel-8-for-x86_64-appstream-aus-rpms --enable openstack-17.1-for-rhel-8-x86_64-rpms
        subscription-manager release --set=8.4
     UpgradeLeappCommandOptions: "--enablerepo=rhel-9-for-x86_64-baseos-e4s-rpms --enablerepo=rhel-9-for-x86_64-appstream-e4s-rpms --enablerepo=rhel-9-for-x86_64-highavailability-e4s-rpms --enablerepo=openstack-17.1-for-rhel-9-x86_64-rpms --enablerepo=fast-datapath-for-rhel-9-x86_64-rpms"

   Note

   If your deployment includes Red Hat Ceph Storage nodes, you must add the CephLeappRepoInitCommand parameter and specify the source OS version of your Red Hat Ceph Storage nodes. For example:

   CephLeappRepoInitCommand:
   ...
     subscription-manager release --set=8.6

3. Add the LeappInitCommand parameter to your system_upgrade.yaml file to specify additional requirements applicable to your environment, for example, if you need to define role-based overrides:

     LeappInitCommand: |
       subscription-manager repos --disable=*
       subscription-manager release --unset
       subscription-manager repos --enable=rhel-9-for-x86_64-baseos-e4s-rpms --enable=rhel-9-for-x86_64-appstream-e4s-rpms --enable=rhel-9-for-x86_64-highavailability-e4s-rpms --enable=openstack-17.1-for-rhel-9-x86_64-rpms --enable=fast-datapath-for-rhel-9-x86_64-rpms
       leapp answer --add --section check_vdo.confirm=True
   
       dnf -y remove ruby-irb

   Important

   Removing the ruby-irb package is mandatory to avoid a conflict between the RHEL 8 ruby-irb directory and the RHEL 9 symlink. For more information, see the Red Hat Knowledgebase solution leapp upgrade RHEL8 to RHEL9 fails with error "rubygem-irb-1.3.5-160.el9_0.noarch conflicts with file from package ruby-irb-2.5.9-110.module+el8.6.0+15956+aa803fc1.noarch".

   Note

   If your environment previously ran RHOSP 13.0 or earlier, during the system upgrade, a known issue causes GRUB to contain RHEL 7 entries instead of RHEL 8 entries. For more information, including a workaround, see the Red Hat Knowledgebase solution Openstack 16 to 17 FFU - During LEAPP upgrade UEFI systems do not boot due to invalid /boot/grub2/grub.cfg.

4. If you are upgrading Red Hat Ceph Storage nodes that originated in RHOSP 16.1 and earlier, add the CephStorageLeappInitCommand parameter to remove fencing agents:

     LeappInitCommand: |
       ...
   
       dnf -y remove ruby-irb
   
     CephStorageLeappInitCommand: |
       ...
   
       dnf -y remove ruby-irb fence-agents-common

5. If you use kernel-based NIC names, add the following parameter to the system_upgrade.yaml file to ensure that the NIC names persist throughout the upgrade process:

   parameter_defaults:
     NICsPrefixesToUdev: ['en']
   ...

6. Run the Leapp upgrade:

   $ openstack undercloud upgrade --yes --system-upgrade \
   /home/stack/system_upgrade.yaml

   Note

   If you need to run the Leapp upgrade again, you must first reset the repositories to RHEL 8.

7. Reboot the undercloud:

   $ sudo reboot