online migration status between differnt kernels

[pille]

hi,

i just did a online migration of a KVM machine from kernel 2.6.32 to 2.6.18, which failed.
however the log is a bit ambiguos:

/usr/bin/ssh -t -t -n -o BatchMode=yes 192.168.2.11 /usr/sbin/qmigrate --online 192.168.2.11 106
Mar 05 12:41:06 starting migration of VM 106 to host '192.168.2.11'
Mar 05 12:41:06 copying disk images
Mar 05 12:41:06 starting VM on remote host '192.168.2.11'
Mar 05 12:41:07 starting migration tunnel
Mar 05 12:41:07 starting online/live migration
Mar 05 12:41:09 migration status: failed
Mar 05 12:41:11 migration finished successfuly (duration 00:00:05)
Connection to 192.168.2.12 closed.
VM 106 migration done

other direction is the same.
shared storage is NFS, migration between pure 2.6.18 works fine

 

[tom]

migration between different kernel version (in this case also different KVM) is not possible.

 

[pille]

that's ok, but i'd like to file a bug against the ambiguous status. especially since the last line indicates success.
additionally i'd like to file a feature request to check for incompatible software before online migration. as i remember correctly something like that is already done, if you're not using a shared storage. just define constrains for working online migration, since the cluster knows all kernel versions. if you'd think further, you can make the cluster master aware of all pveversion-outputs and define supported migration scenarios without the need to care about the other paths ;-)