@dinhngtu Seems like an issue for this already exists: https://github.com/xcp-ng/xenadmin/issues/260
Added what I wrote above as a comment.
Gnggi created this issue in xcp-ng/xenadmin
open
Showing wrong Virtualization state for VMs with Management agent 9.1.100
#260
Live migrate should work from old to new, so as soon as your master is on 8.3, if you have a slave in 8.2.1 for example, you can evacuate VM from this host to any host.
So you should be able to live migrate all VMs from a slave on 8.2.1 toward the master on 8.3.
NOT_SUPPORTED_DURING_UPGRADE() means there's something else in play, I would try to live migrate with xe CLI to get more details on the issue.
From another post I gathered that there is an auto-scan feature that run by default every 30 seconds which seems to cause a lot issue when the storage contains a lot of disks or you have a lot of storage.
It is not completely clear if this auto-scan feature is actually necessary and to some customers Vates helpdesk has suggested to reduce the frequency of the scan from 30 seconds to 2 minutes and that seems to have improved the overall experience.
The command would be this:
xe host-param-set other-config:auto-scan-interval=120 uuid=<Host UUID>
where UUID is the pool master UUID.
Of course I won't run that in production without Vates support re-assurance that doing so it won't have a negative impact but I think is worth mentioning this.
In my situation I can see how frequents scan would cause delay on the other tasks considering that effectively my system is always under scanning with probably the scan task itself being affected by it.
