Good question about the log. There may be something in /var/log/messages on the new node.
If not, when you restore from the new backup, I would expect the same error on start. In that case, however, you might get more detail on startup than you would for the migration.
Now I'm thinking aloud here. Remember the limitations of my knowledge and how easily I get confused please. BUT:
/etc/sysconfig/iptables-config (on a Virtuozzo Hardware Node) defines which iptables modules are loaded on the hardware node itself. If a particular module isn't loaded on the hardware node itself then it can't be loaded in a Container no matter what.WARNING:
On Centos 6 and probably other flavours, unless /etc/sysconfig/iptables exists (even with no content), then /etc/sysconfig/iptables-config will not get looked at (iptables won't be loaded) and this means none of the iptables modules that you may have specified in that file will actually get loaded on the HN. In turn, this will cause problems with any Containers that make use of any significant sort of firewall because the modules will not be available.
/etc/sysconfig/vz file on a Virtuozzo Hardware Node defines....what? The modules that are enabled by default in a Container, I think. This should be the same as, or a subset of, the modules defined in /etc/sysconfig/iptables-config
Modules defined in /etc/sysconfig/iptables-config but not /etc/sysconfig/vz can be loaded on a per-container basis via the Container's individual configuration file.
My advice: make sure /etc/sysconfig/iptables-config and /etc/sysconfig/vz on the new node have the same (or more) modules as on the old node AND make sure those modules are actually loading by using lsmod | grep 'name of module'. If they are not, check that iptables itself is loading, if necessary by creating a blank /etc/sysconfg/iptables file
Here's a link to the KB that deals with how to use APF in a Container, in case it is useful in terms of which minimum set of modules are essential: http://kb.parallels.com/en/875