While searching the web for how to perform PCI-Passthrough on XenServers, we mostly get info about previous versions. Since I have just completed setting up PCI-Passthrough on XenServer version 6. 5 (with recent update 8, just to give you some notion of the exact time frame), I am sharing it here.
Hardware: Cisco UCS blades, with fNIC. I wish to pass through two FC HBAs into a VM (it is going to act as a backup server, and I need it accessing the FC tape). While all my XenServers in this pool have four (4) FC HBAs, this particular XenServer node has six (6). I am intending the first four for SR communication and the remaining two for the PCI Passthrough process.
This is the output of ‘lspci | grep Fibre':
0b:00.0 Fibre Channel: Cisco Systems Inc VIC FCoE HBA (rev a2)
0c:00.0 Fibre Channel: Cisco Systems Inc VIC FCoE HBA (rev a2)
0d:00.0 Fibre Channel: Cisco Systems Inc VIC FCoE HBA (rev a2)
0e:00.0 Fibre Channel: Cisco Systems Inc VIC FCoE HBA (rev a2)
0f:00.0 Fibre Channel: Cisco Systems Inc VIC FCoE HBA (rev a2)
10:00.0 Fibre Channel: Cisco Systems Inc VIC FCoE HBA (rev a2)
So, I want to pass through 0f:00.0 and 10:00.0. I had to add to /boot/extlinux.conf the following two entries after the word ‘splash’ and before the three dashes:
Initially, and contrary to the documentation, the parameter pciback.hide had no effect. As soon as the VM started, the command ‘multipath -l‘ would hang forever (or until hard reset to the host).
To apply the settings above, run (for a good measure. Don’t think we need it, but did not read anything about it): ‘extlinux -i /boot‘ and then reboot.
Now, when the host is back, we need to add the devices to the VM. Make sure that the VM is in ‘off’ state before doing that. Your command would look like this:
xe vm-param-set uuid=<VM UUID> other-config:pci=0/0000:0f:00.0,0/0000:10:00.0
The expression ‘0/0000′ is required. You can search for its purpose, however, in most cases, your value would look exactly like mine – ‘0/0000′
Since my VM is Windows, here it almost ends: Start the VM, and if it boots correctly, Install Cisco VIC into it, as if it were a physical host. You’re done.