3

I installed a fresh CentOS 7.2 guest (babybrighton) on my host (brighton), and then did this from brighton (where /dev/sdb is a physical device connected to brighton):

virsh attach-disk --persistent babybrighton /dev/sdb vdb

This worked fine and the disk shows up fine:

[root@babybrighton ~]# ls -l /dev/vdb* 
brw-rw----. 1 root disk 252, 16 Dec  4 20:37 /dev/vdb 
brw-rw----. 1 root disk 252, 17 Dec  4 20:37 /dev/vdb1 
brw-rw----. 1 root disk 252, 18 Dec  4 20:37 /dev/vdb2 
brw-rw----. 1 root disk 252, 19 Dec  4 20:37 /dev/vdb3 

I now want virsh snapshot-create-as to save babybrighton's state and the data on /dev/vda*, the psuedo-disk I made when creating babybrighton.

However, I do not want virsh snapshot-create-as to save the state of /dev/vdb* on babybrighton, because /dev/sdb is an 8TB drive on brighton that holds the babybrighton VM itself.

I do want the snapshot to remember that it's mapping /dev/vdb to the host's /dev/sdb, but that's the only information about /dev/vdb that the snapshot should have.

I've tried things like:

virsh snapshot-create-as --diskspec=vda,snapshot=internal --diskspec=vdb,snapshot=no babybrighton test1 "semi external disk"  

# result 

error: unsupported configuration: disk 'vdb' must use snapshot mode 'internal' 

and many similar, but haven't found anything that works, or even if this is possible.

I need /dev/vdb available when babybrighton boots, so I can't just run a command after I log into babybrighton.

Is there any easy way to accomplish this?

If not, what's a good way to keep /dev/vda* synced so I can rollback when needed?

Does VirtualBox handle this better?

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy