Hello all,
Newbie on FRR and also Babel 

I made a test setup as 

2 frr routers 
They have 2 interfaces in common subnet..
and a 3rd interface which only belongs to each router seperately..

First i tried the config with ospfd
The 3rd interface routing appeared correctly and 1st router was able to ping 3rd interface of the other router (and vice versa) 

Then i wanted to test babel..
Disabled ospfd
Made an example config for babel

!
!
interface eth0
 babel hello-interval 100
!
interface eth2
 babel wired
 babel hello-interval 100
!
interface eth1
 babel hello-interval 100
!
!
router babel
 network eth0
 network eth1
 network eth2
 redistribute ipv4 connected


When starting FRR i am getting the following errors

Starting Frr daemons (prio:10):. zebra2018/10/18 17:59:30 warnings: ZEBRA: [EC 4043309104] Disabling MPLS support (no kernel support)
. babeldThere is same network configuration eth0
There is same network configuration eth1
There is same network configuration eth2

eth0 : common interface 10.1.1.231-10.1.1.232
eth1:  seperate interface 192.168.20.1  / 192.168.21.1
eth2:  common interface 192.168.30.1 / 192.168.30.2

Here is the routing :

0.0.0.0         10.1.1.1        0.0.0.0         UG        0 0          0 eth0
10.1.1.0        0.0.0.0         255.255.255.0   U         0 0          0 eth0
192.168.20.0    0.0.0.0         255.255.255.0   U         0 0          0 eth1
192.168.30.0    0.0.0.0         255.255.255.0   U         0 0          0 eth2

after a second

0.0.0.0         10.1.1.1        0.0.0.0         UG        0 0          0 eth0
10.1.1.0        0.0.0.0         255.255.255.0   U         0 0          0 eth0
192.168.20.0    0.0.0.0         255.255.255.0   U         0 0          0 eth1
192.168.21.0    10.1.1.232      255.255.255.0   UG        0 0          0 eth0
192.168.30.0    0.0.0.0         255.255.255.0   U         0 0          0 eth2


As you see routing seem ok after a second..
but on next second it dissapears.
So do ping..

PING 192.168.21.1 (192.168.21.1) 56(84) bytes of data.
ping: sendmsg: Network is unreachable
64 bytes from 192.168.21.1: icmp_seq=4 ttl=64 time=1.58 ms
64 bytes from 192.168.21.1: icmp_seq=6 ttl=64 time=0.751 ms
ping: sendmsg: Network is unreachable
64 bytes from 192.168.21.1: icmp_seq=8 ttl=64 time=0.868 ms


Here is the output of babel interface

ospfd-3# sh babel route 
10.1.1.0/24 metric 65535 refmetric 0 id f2:e7:01:ff:fe:4e:47:eb seqno 52317 age 2 via eth1 neigh fe80::986c:adff:fef9:5113 nexthop 192.168.21.1 (feasible)
10.1.1.0/24 metric 65535 refmetric 0 id f2:e7:01:ff:fe:4e:47:eb seqno 52318 age 1 via eth2 neigh fe80::9885:8cff:fe66:8028 nexthop 192.168.30.2 (feasible)
192.168.21.0/24 metric 65535 refmetric 0 id f2:e7:01:ff:fe:4e:47:eb seqno 52318 age 1 via eth1 neigh fe80::986c:adff:fef9:5113 nexthop 192.168.21.1 (installed)
192.168.21.0/24 metric 65535 refmetric 0 id f2:e7:01:ff:fe:4e:47:eb seqno 52318 age 1 via eth2 neigh fe80::9885:8cff:fe66:8028 nexthop 192.168.30.2 (feasible)
192.168.30.0/24 metric 65535 refmetric 0 id f2:e7:01:ff:fe:4e:47:eb seqno 52317 age 2 via eth1 neigh fe80::986c:adff:fef9:5113 nexthop 192.168.21.1 (feasible)
192.168.30.0/24 metric 65535 refmetric 0 id f2:e7:01:ff:fe:4e:47:eb seqno 52318 age 1 via eth2 neigh fe80::9885:8cff:fe66:8028 nexthop 192.168.30.2 (feasible)
10.1.1.0/24 metric 0 (exported)
192.168.20.0/24 metric 0 (exported)
192.168.30.0/24 metric 0 (exported)