Comment 6 for bug 1174591

Ahh, understood Kevin, yes, if the network backend has control over that,
then it shouldn't be a problem.

But it's a problem if this features is used blindly, so I think it'd be ok if
we provide a setting to enable/disable this feature, and we set it disabled
by default, so, the deployer can enable it if he knows what he's doing
in combination with certain backends.

And yes, we have run into that scenario during testing, It happened to us
when a network node ran out of memory (lots and lots of networks) and
the neutron-l3-agent was killed by OOM, all the underlaying qrouters kept
working, but the neutron-l3-agent stops replying to heartbeats and routers
got moved elsewhere.

With pacemaker, in that specific situation, netns-cleanup --forced and ovs-cleanup
forced would be started, but there are chances they have no memory /resources either.

In a last take, IPAM reboot will happen, and, yes, you're right that it's slow, but it
will only fail for a ~1 minute or so.