Hosts not auto balancing in pool
Systemgeek-louis last edited by Systemgeek-louis
I have a pool of 4 identical hosts all running XCP 8.2.1 and using NFS shared storage for the VMs. When I export from an older pool a VM then import it in to the new pool the VMs do not auto balance in the pool.
When we start up a vm and not select where to start it. It tries to start the vm on the first pool member. Then fails when that pool member is out of memory.
In previous versions it would start it on the pool member with the most free memory.
Danp Top contributor 💪 last edited by
Are you expecting this to be managed by the
load-balancerplug-in or something else?
- XAPI will try to place VMs on boot to the right server, at least a machine with enough memory
- If it's not the case and ALWAYS starting on the same host even when it's full, it means you other costs aren't a potential destination for various reasons (SR not connect on the other hosts for example)
- XAPI will only place VMs on boot, after that, you need an orchestrator to manage this.
So now that I am doing this myself rather then listening to some one else explain it to me. Here is whats happening.
We have 2 pools. When I Live migrate from pool01 (which is running an xcp 7.6) to pool02 running xcp 8.2.1. We do the migration with the Migration Wizard. Ever Live migration like this sends the vm to the pool master on pool02. And when the pool master exceeds CPU or Memory utilization the migration will fail and send it back.
Should it not Live migrate from pool to pool to other pool members not just the pool master?
Also, once migrated to the pool master I can then Live migrate again to another host in the pool just fine. So its not a resource issue.
- It can't be a CPU over-provisioning issue, since there's no limit on that side.
- How do you make the migration exactly? What wizard are you talking about, using which client?
Using XCP-ng Center ( am on version 20.04.01). If I right click on a running VM then click on Migrate to Server and then Migrate VM Wizard.
Could you try with a supported client?
Huh??? Is not XCP-ng Center a supported client?
I cannot use XOA because no one in the company wants to pay for that..
What other client is there?
I hate to say that, but reading the fine manual is a good step to start: https://xcp-ng.org/docs/management.html
Not paying is fine, but then the company will pay your time spent understanding all of this. Using XOA might be cheaper in the end, but hey, it's not up to me
Actually I have read that. And unless I am mistaken XOA (in all its forms. WebUI, CLI and API) are for pay. I did not see that XCP Center was community based. And that finally leaves doing it using XE Cli (XAPI). Not a very good way to do things.
But I think we are getting off the point here. My question is is there a limitation in XCP Center ( or a bug) that is causing this? We can work around it by doing 2 migrations. First to the pool master and second to some where else in the pool.
If you read it more carefully, just by clicking on the XO link in that list, you would have found this: https://xcp-ng.org/docs/management.html#xen-orchestra and then see:
XOA vs XO from GitHub?
XOA is meant to be used as the easiest way to test it, but also to use it in production: this is the version professionally supported. If you are an individual, feel free to enjoy version from GitHub directly!
Then, after a minimal effort, going to https://xen-orchestra.com/docs/installation.html#from-the-sources and understood that you can have all XO features for free if you build it from Github.
Sometimes I wonder, we made such efforts to keep things fully open source, with just spending few minutes to search for how to get everything for free is already too much sometimes
Without talking about another company which can't afford to use a decent tool to manage and backup their VMs
Yes but under that it says that building it your self is not so easy unless you have built Nodejs apps before. I have not.
But I would be willing to try.
Anyway. For what we are doing (pool migration) its going fine. And we are just about done. Once done I am going to destroy the old pool and rebuild it as part of the new pool.
But thank you for your help.
The deal is simple:
- if you don't want to pay, you have to make some minimal efforts to enjoy all features for free
- if you don't want to make efforts, you usually pay for it
You can't have both
For the migration, I don't have any obvious answer, I don't think it's a normal behavior, but I'm not sure what XCP-ng Center does.
Yes you are quite right. But its not my money to spend. If it were left up to me I would spend it. Since XCP seems to be lots and lots and lots of times better then VMWare for what you pay for even when you have to pay.
There is no way to compare pricing. But not my company not my money. And no one asks or seems to want my option.
Don't worry, I don't blame you, but the people taking the decision to pay or not