Question about Continuous Replication/ Backups always doing Full Backups

Kraken89

I am currently working on trying to setup continuous replication from one host to another. I have the process setup and it does replicate the VMs from the local storage of server 1 to local storage of server 2 but every time the job runs, it runs a full back up. It was my understanding that it runs a full backup the first time and then does a delta every time after based on the schedule.

I am currently on this version of the XOA vm.

I have done the following to try and troubleshoot it.

Set the replication retention to both 1 or more.
Verified that Force Full Backup option is NOT checked on the schedule.
Verified that the Purge snapshot data when using CBT. is NOT checked. I don't currently use CBT as well but made sure it was unchecked as well.
Full backup interval is not set.

I could also be mistaken on how this process should be run. Any help would be appreciated.

florent

@Kraken89 is it on all VM or only one ?
we did quite a lot of changes on the replication, maybe we missed something.

are you replicating inside the same pool or toward another pool ? (are both server in the same pool ? )

Andrew

@florent I too am having issues with this... on some VMs...

Running XCP 8.3 (latest March update), XO (master 0286f).

I have a simple small CR job that replicates 3 VMs between two pools. Two VMs got stuck at Full, and one works correctly. CBT/NBD 1 enabled. Purge disabled.

It's also leaving snapshots each time. No CD in the drive this time.

I'll have to update XO and try again.

Kraken89

@florent Hello!

The VMs are replicating within the same pool. The pool only has 2 hosts and all is taking place within the same pool.

All the VMs currently live on host 1 with the local storage. The VMs are set to replicate to the local storage on host 2.

ph7

since I had my problem fixed in
https://xcp-ng.org/forum/topic/11969/timestamp-lost-in-continuous-replication/22
I tested my f5468 commit similar to Your setup with 2 Hosts in the same pool and local storage, ran CR with retention of 2 from 1 host to the other and it worked as expected.
One full and then delta.

Andrew

@florent I updated XO to master 60ba5, and still having the issue.

I don't see any errors in the backup log. It just says "isFull": true for the ones stuck on full backups.

The XO log just reports:

Mar 24 16:26:47 xo1 xo-server[21199]: 2026-03-24T20:26:47.315Z xo:backups:worker INFO starting backup
Mar 24 16:26:52 xo1 xo-server[21199]: 2026-03-24T20:26:52.359Z xo:xapi:xapi-disks INFO export through vhd
Mar 24 16:26:54 xo1 xo-server[21199]: 2026-03-24T20:26:54.410Z xo:xapi:xapi-disks INFO export through vhd
Mar 24 16:29:22 xo1 xo-server[21199]: 2026-03-24T20:29:22.250Z xo:backups:worker INFO backup has ended

Note, it reports two export through vhd and does two full backups and one delta.