Today I rebooted a xen host, everything came back up as I would expect, and after trying to live migrate VMs back onto the host I got this error message.
Internal error: File "xapi_xenops.ml", line 1788, characters 3-9: Assertion failed
I thought it was something wrong with xencenter, but then tried via command line and got this error:
Error code: SR_BACKEND_FAILURE_46 Error parameters: , The VDI is not available [opterr=VDI SOME-UUID already attached RW]
The message “The VDI is not available” I’ve seen many times before and I knew what to do.