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We have a XenServer pool consisting of two Dell R410's running XenServer 5.6. The servers are connected to a few iSCSI NAS devices.

Lately, as I've been looking at the /var/log/messages I've been seeing a lot of this:

Apr  6 12:01:27 xenserver-alpha xapi: [error|xenserver-alpha|345 xal_listen|Event thread updating guest metrics (domid: 87) D:7cfbb800692e|sql] Duplicate key in set or map: table VM; field platform; ref OpaqueRef:b6808180-fabd-07c7-d19c-df3e345e8854; key viridian

I'm not sure what this error message means. I've seen it on both XenServers (lets call them xenserver-alpha and xenserver-beta).

Googling as brought me a few posts on the XenServer forums, but none of them seem to answer my question, which is:

What does this error mean?

Should I be concerned about it?

How do I fix it?

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up vote 1 down vote accepted

The "error" is entirely harmless. You should not be concerned and no fix is necessary.

It relates to an old feature where the "viridian" flag had to be automatically set on certain VMs. FYI the "viridian" flag modifies the CPUID results inside the guest, triggering the OS to use certain optimisations when running on a hypervisor.

For reference the code generating the error is here:

We (the xapi developers) ought to tidy up some of these spurious "error" messages. If you would like to help, join the mailing list and say hi! :)

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