@jedimarcus Got it, thank you again. Labeling that part of the settings as 'Servers' is a bit confusing in this case. Perhaps the XO team might want to label that as 'Pools' instead?

@jedimarcus One pool, two host servers. So in that situation, you only need to connect the master server? Interesting. Thank you for the info!

@jedimarcus I tried disabling and then re-adding one of the servers by IP, this failed with a message that the server already exists.

@Danp This worked, but I had to disable all the servers, then start by re-enabling the master server first. If you didn't do so, the master couldn't re-join because XO thought the pool was already there.

Thank you folks, for your help. Looks like I just need to add the disable/re-enable bit to the process when changing credentials.

@jedimarcus I thought of doing so and that was to be my next step, but I was afraid that this would mess up my configured backups. I'd rather find a solution to the particular problem and not mess up the backups if I can, rather than having to give up and delete/re-add.

@jedimarcus It's the authentication failure message.

SESSION_AUTHENTICATION_FAILED(root, Authentication failure)

It's there before I change the credentials, and even though the green check seems to indicate that I've successfully changed them, apparently there's still an authentication failure. It seems as though XO is not properly saving the changes to the credentials.

Good day. As part of our security plan I periodically change the access credentials on all of our servers, including the ones hosting XO and our VM environments. A few days ago I changed the root passwords on our XCP-ng servers, and since doing so am having issues getting XO to connect to them.

When coming to the XO home area, I'm presented with this:

Naturally, I go to Settings - Servers, to check and the credentials aren't working, as one would expect:

SESSION_AUTHENTICATION_FAILED(root, Authentication failure)

So I go to the password field and enter the updated credentials. XO gives me a green checkmark, which I would expect means that the credentials are accepted.

However, the problem still persists. XO acts as though it doesn't have the correct credentials, and I'm unable to view/manage the servers or VMs.

If I'm missing a step here, please let me know! Not sure how to proceed at this point. I know the credentials are correct, as everything functions normally in the "heavy" Windows management client.

Quite welcome, @mhrsolanki2020 . I am a frequent searcher for knowledge, so happy to be able to pass along something helpful.

And @akurzawa , I'm aware it's not an issue with XCP/XOA, it was, as I said, my own ignorance. Just hoping to help other folks out in the future. Thank you for the advice about LVM, in this case it just happened to be what was originally running on the VM.

I have a much better understanding of how that works now, thank you Olivier. My compliments to Jon, once he overcame his surprise at how little I knew, he was kind enough to point me in the right direction.

As I am a relative newcomer to Linux administration, and most power users suffer from the curse of knowledge, occasionally I run across issues that are so trivial to the experts that it's difficult for me to find help for them. In case it would help someone else in the future, I thought I would post this particular one here.

I use both Borzel's excellent XCP-ng Center as well as XOA to administer my systems, but in this case was using XOA. What I needed to do was increase the size of the disk being used by a VM running Ubuntu from 4GB to 24GB. Easy, right? I just change that in XOA and I'm done. Of course, that wasn't all there was to it, as the VM doesn't recognize the additional space.

Thinking (in ignorance) that there was a problem with my XOA, I chatted with Jon in support. I'm sure he must be convinced that I'm an idiot, but he was kind enough to explain to me that there were additional steps involved to get the allocated space to be recognized by the VM. He suggested a couple of places to read up on this that didn't end up having what I needed, but I eventually found the correct procedure here:

https://www.rootusers.com/lvm-resize-how-to-increase-an-lvm-partition/

Hopefully that will be of assistance to someone else in the future.