CBT disabling itself / bug ?
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Hi,
Latest XOA, with fully patched XCP 8.3 here.
I'm fiddling around again with NBD+CBT in backup jobs (was avoiding CBT for a time, to reliably control my backups and avoid unnecessary KEY points) in the context of THICK SRs to spare some space.
I know that CBT is reset when migrating from one SR to another.
But here is what I encounter :
- VM has no CBT enabled on its VDIs, it is on a SHARED SR in a pool of 3 hosts
- backup option changed for NBD+CBT, was only NBD before
- CBT is enabled on the next run by the backup job, I get a delta (was expecting a FULL ?)
- next run, delta, as expected
- i migrate this VM on another HOST, without changing its SR
- CBT is immediatly disabled ? why ??
- next run of backup it tries a delta, but "fall back to a full" (normal as CBT has been disabled...), and do a KEY point on the remote
- next run is a delta as expected
does this mean if I do a rolling pool update or host maintenance that will move the all VMs around, all CBT will be disabled and I should expect a FALL BACK TO FULL on all my NBD+CBT enabled backup jobs ??!
why disabling CBT on a change of HOST and no move of SR ?