Interrupt Received on invalid vector

Hi,

I've just upgraded an HP DL580 G7 using the customised HP image from ESXi 5.1 to ESXi 6.0 update 1a.

Everything appears to be fine, however when I check the events tab of the ESX host the following informational/warning event is being displayed:

Alarm 'host error' on [hostname] triggered by event [xxxx] 'Issue detect on [hostname} in NS:Intrcookie 3411.

Interrrupt received on invalid vector (cpu 34, vector 70); ignoring it

I've also upgrade an identical host which is not showing the same symptoms.

Can anybody shed any light on this matter?

Thanks