[Babel-users] babeld flushes routes and they never come back until restarted

[Juliusz Chroboczek]

> We have moved to version 1.4.3 and still issues persist.

Sorry for the delay, Harshal, I was very busy.

You appear to be having two unrelated issues, and it's very difficult
to work out what's going on from your somewhat confused descriptions.
I would suggest first getting a pure mesh to work (without gateways),
and only then to try adding your DHCP/NAT-ing stuff.

> Once I restart the master machine (where I run babeld with "-C
> 'redistribute metric 128'") either all the routes come back on all the
> devices or all the devices get negative routes and they are never
> fixed. (waited for half hour).

That's most probably a DHCP issue.  Most DHCP clients don't install
a default route if there's already one, and will not install a new
default route if the previous default route disappears.

The basic issue is that that's not what DHCP is designed for -- it's
designed for configuring end hosts, not routers.  The right solution
would be to have a statically configured address and route on your
gateway; if you insist on running DHCP on the gateway, you could
partially work around it by doing

  in ip 0.0.0.0/0 le 0 deny

> Every few minutes, we keep getting negative routes in the routing
> table and then routes correct themselves.

Have you definitely ruled out your interfaces going down-up because of
hardware problems?  Babeld will flush all routes that go through
a downed interface, and will take up to a dozen seconds in its default
configuration to recover.

You can work around the issue by reducing the hello interval.  But
there's only so much that can be done with unreliable hardware.

Sorry I cannot be of more help, but there's only so much that can be
debugged remotely.

-- Juliusz