Upgrading UC nodes one by one is a thing of the past. Prime Collaboration Deployment (PCD) is the best tool for upgrades, allowing you to upgrade the cluster and switch versions from the same place. I’m a big fan of PCD. However, I believe Cisco is moving towards integrating all PCD capabilities into CUCM as a native option, aiming to phase out PCD.
From a cost perspective, this is a good move for Cisco as it eliminates the need to maintain a separate development team for PCD, and integrating everything natively into CUCM can save costs.
This blog is about performing a cluster upgrade using the cluster upgrade option available on CUCM. CUC has not been capable of doing an upgrade using the Cluster Upgrade yet. I expect they will bring this to CUC soon.
Before going with any upgrade, I would recommend reading the following and running the Upgrade Readiness COP files to make sure there are no failed test cases which can cause the upgrade to fail:
- Release notes
- Read Me Guide
- Install/Upgrade Guide
Note :- Make Sure the backups are taken before the upgrade.
Before I move forward to explain how to perform the upgrade, let me give a nutshell overview of the different types of upgrades:
- Direct Standard Upgrade: A standard upgrade where you need to upgrade the application software, but not the underlying operating system. This is usually the simplest form of upgrade and typically applies to upgrades within the same major-minor release category, where the OS is the same for both releases.
- Direct Refresh Upgrade: A direct upgrade where you need to upgrade both the application software and the underlying operating system software. This is typically used if you’re upgrading from one major-minor release to another where the OS is different for the two releases.
Let us split the task of upgrading the cluster using the Cluster Upgrade option:
TASK 1 Run Upgrade Readiness COP File (Pre-upgrade): Check system connectivity and health. Fix any issues before proceeding. (I will make another blog on how to use the Upgrade Readiness COP)
TASK 2 Configure Clusterwide Reboot Sequence: Specify the reboot sequence to minimize downtime.
- Login to the CUCM OS Admin.
- Select Restart/Switch-Version Cluster.
- Choose the sequence you need and click Save.
TASK 3 Configure Cluster Software Location: Set up the software location details for all nodes in the cluster.
The software location must be configured so that the nodes can find the files for the upgrade. This can be remote or local and can be defined for the whole cluster or individually for each node. There could be a situation where two nodes are in one data center and others in another data center over the WAN. In that case, we can set up an SFTP locally for the files for the data center that is separated, instead of sending the files over the WAN.
In this blog, I use the same location for the whole cluster. And I’m performing and Direct standard Upgrade.
- Login to the CUCM OS Admin.
- Select Cluster Software Location.
- Choose the Node and click on Go
- Provide the details. If you are using the same location for all nodes, select “Apply to all Nodes.” If not, repeat the process for each node individually.
Note: You can choose the “Continue with Upgrade after Download” option so that the upgrade starts automatically once the files are downloaded. If not selected, CUCM will ask for your confirmation to proceed with the upgrade after the files are downloaded.
Additionally, you can choose the “Switch Version Cluster after Upgrade” option so that you don’t need to switch versions manually. However, I personally recommend keeping this option unselected if you prefer to switch versions later once the upgrade is completed for the whole cluster.
- Test access to software location.
Note: You cannot perform the “Test access to software location” if you opted for the “Apply to all Nodes” option. Testing is possible only if you unselect it. To ensure reachability, I have unselected the “Apply to all Nodes” option and run the test.
TASK 4 Upgrade the Cluster: Use either OS Admin or CLI. You can switch versions automatically during the upgrade or save the upgraded version to the inactive partition.
- Login to the CUCM OS Admin.
- Select Install/Upgrade Cluster.
- Click on Next.
- A dropdown option will be displayed; select the files for the upgrade.
Note: You will find the files only if they are valid. So make sure the proper files are being used.
- Click on Next.
- The process of downloading will start.
- Once the download is completed for all nodes, the installation will start.
Note: The installation has started because we chose the option to “Continue Upgrade after Download” in the software location. If this was not selected, you would be asked to confirm before proceeding with the upgrade.
- Once Installation has been Completed proceed with The switch version.
TASK 5 Switch Version Manually (Clusterwide): If not done automatically, switch versions manually.
Note: The active and inactive versions will be displayed. Make sure it shows the correct one before switching.
TASK 6 Run Upgrade Readiness COP File (Post-upgrade): Check the system’s health post-upgrade. (I will make another blog on how to use the Upgrade Readiness COP post-upgrade)