This article contents known reasons of migration failures.
Contents
Problem #1
Symptoms
After giving vzmigrate -v --online <ip address> <veid> the following message appears:
Error: undump failed: Invalid argumentStopping VE ... Restoring failed: iptables-restore exited with 1 rst_restore_net: -22
Reason
The VE which you wish to migrate uses some iptables modules, that are not loaded on destination node. Consequently iptables-restore fails.
Workaround
Load all iptables kernel modules that are used by VE on destination node.
Links
Problem #2
Symptoms
The system runs 028stab031 or older kernels and after giving vzmigrate -v --online <ip address> <veid> the following message appears:
Live migrating VE
Suspending VE
Setting up checkpoint...
suspend...
Can not suspend VE: Device or resource busy
file on unsupported FS: magic 0bad1dea
Checkpointing failed
Error: Failed to suspend VE
Reason
The VE which you wish to migrate uses inotify mechanism (magic 0bad1dea), that is not supported by 028stab031 and older kernels.
Workaround
Update till 028stab035 or newer kernel.
Links
- http://bugzilla.openvz.org/show_bug.cgi?id=552
- http://forum.openvz.org/index.php?t=tree&goto=14780&#msg_14780
Problem #3
Symptoms
After giving vzmigrate -v --online <ip address> <veid> the following message appears:
Dumping VE
Setting up checkpoint...
join context..
dump...
Can not dump VE: Device or resource busy
unsupported netdevice tun0
Checkpointing failed
Error: Failed to dump VE
Reason
Checkpointing doesn't support tun device inside VE, which is usually used for VPN via the TUN/TAP device in VE.
Workaround
You should not use tun device in VE to migrate it. If you're using VPN in VE, just stop VPN, then produce the online migration and after that start the VPN. Of course, all current connections to VPN will be lost :(.