Patching to a specific version

mauzilla

We're migrating our VM's to 2 new hosts (non-pool hosts) - The 1 pool has been live now for 2 months and I can see there are patches to be installed:

8.2.1
release/yangtze/master/58

We're busy setting up the next host and there will be initial patching. How can I setup the new host and patch it to the same version above so that we're able to have these 2 hosts on the same patch level? We're unable to shutdown the old host as there is too many running VM's and want to ensure we don't have differences in the versions.

Using the XOA can this be done or would we need to update using the command line? And if so, how can I achieve this?

olivierlambert

XCP-ng isn't meant to be at a "specific patch" level, by design. @stormi might provide some details, but at least you know it's not meant to do this

mauzilla

@olivierlambert off course and accept it that way, just trying a workaround as 2 of the 3 hosts now is on the same level (with 5 due patches) - Updating the 3rd (new host) will install it with the newest patches, which will lead to us not being able to migrate VM's between the 3. Hoping there is a way to get the 3rd one patched to this level, or how does XCP manage the migration check, does it include patches aswell or does it look at the version 8.2.1 (which is the latest)?

mauzilla

So after the install I can see the version and build is already the same (master/58 8.2.1), but the new host has 45 patches to be installed. Does the individual patches also influence the migration restriction or do you look at the build / version?

stormi

We don't have an easy way to bring a new host to the update level of the coordinator host when the coordinator is not up to date.

But it's doable nonetheless: get the versions of installed RPMs on the coordinator host with rpm -qa | sort and then use this list as an input for yum update on the new host.

Then compare the outputs of rpm -qa | sort between the coordinator and the updated host to make sure everything is fine.

And then update all hosts.

stormi

See https://xcp-ng.org/forum/post/44150

I've got a TODO item to document how to bring a host to the same update level as the coordinator host, but never found or took time to do it.

stormi

@mauzilla said in Patching to a specific version:

So after the install I can see the version and build is already the same (master/58 8.2.1), but the new host has 45 patches to be installed. Does the individual patches also influence the migration restriction or do you look at the build / version?

Cross-pool migration usually works from an older version of XCP-ng towards a more recent one.

splastunov

I made the same trick with rpm -qa to join new host to existing pool, that is not up to date.

mauzilla

works like a charm, thank you gents!