Hey there, apologies for replying to such an old topic but I'm experiencing the same issue and I can't find a newer post.

I have two fresh servers installed with the latest (as of today) ISO - 8.3.0.
I have run yum update on both servers, rebooted both servers.
I can connect to both servers using XCP-ng Center v25.4.0.
I create a pool (using XCP-ng Center) on the first server, which works fine.
I attempt to join the second server to the same pool, it joins but refuses to leave maintenance mode.
XCP-ng Center reports the alert:

XAPI_STARTUP_BLOCKED_AS_VERSION_HIGHER_THAN_COORDINATOR
Xapi startup in pool member <name> is blocked as its xapi version (25.27.0) is higher than xapi version in pool coordinator.

I've checked both servers, there are no updates available via yum update, and I've rebooted both servers since the error occurred.

When I run xe host-param-list on each host to check the version I get the same result for both hosts:

API-version-major: 2
API-version-minor: 21
API-version-vendor: XenSource

Any thoughts?

@olivierlambert Yes, when the host reboots, we're seeing 10+ VMs all configured with the same IP address power up. Where can I confirm that start/start_on is indeed blocked for the DR VMs?

The DR VM has auto_poweron set to true like the source VM:

[root@xcp01 ~]# xe vm-param-get param-name=other-config uuid=41d5dc37-0512-6810-185b-ae7da536cb3b
xo:backup:sr: ac43e953-1c29-f425-5c14-74e5fdb209f6; import_task: OpaqueRef:a7cc8a3f-70b0-42dd-ada5-53d1f1573a1e; mac_seed: 237107d5-1903-5701-11b3-6a6fe9c18dd2; xo:backup:schedule: 0cf32de6-1a4a-49b7-844f-5dea7bb71fd0; xo:backup:job: 7a8da676-e336-49d8-a1ba-02db6990f5a3; xo:backup:vm: e7b0b978-aaa9-a9b3-8079-d13964ab06fd; auto_poweron: true; base_template_name: Other install media; install-methods: cdrom

@julien-f I'm experiencing this as well. I've a remote site running an older version of XCP-ng (7.6). Two hosts without shared storage, Xen Orchestra is configured in Disaster Recovery mode, copying the VMs from one host to the other. It works well, except when the site has a power issue and both the Live and DR VMs power up at the same time.

HA is not configured (no shared storage), to avoid this I need to manually edit the backup VMs and un-tick "Autostart on server boot", but this doesn't work for unexpected outages.

Any suggestions as to what I should check from here?