Query: Routes learned from BGP advertisements not inserted into Kernel FIB and inactive

[sakthishanmugam02]

and show ip route command shows learned route as inactive
B 10.249.64.0/24 [20/0] via 10.249.64.4 inactive, weight 1, 00:16:35

sakthi-vpc-a-vsi# show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP,
       O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
       T - Table, v - VNC, V - VNC-Direct, A - Babel, D - SHARP,
       F - PBR, f - OpenFabric,
       > - selected route, * - FIB route, q - queued, r - rejected, b - backup

K * 0.0.0.0/0 [0/100] via 10.248.64.1, eth0, 01w0d18h
K>* 0.0.0.0/0 [0/0] via 10.248.64.1, eth0, 01w0d18h
C>* 10.248.64.0/24 is directly connected, eth0, 01w0d18h
B   10.249.64.0/24 [20/0] via 10.249.64.4 inactive, weight 1, 00:16:35

and the frr status:

[root@sakthi-vpc-a-vsi ~]# systemctl status frr
● frr.service - FRRouting
   Loaded: loaded (/usr/lib/systemd/system/frr.service; disabled; vendor preset: disabled)
   Active: active (running) since Fri 2022-07-22 18:31:18 EDT; 1 weeks 0 days ago
     Docs: https://frrouting.readthedocs.io/en/latest/setup.html
  Process: 230707 ExecStop=/usr/lib/frr/frrinit.sh stop (code=exited, status=0/SUCCESS)
  Process: 230725 ExecStart=/usr/lib/frr/frrinit.sh start (code=exited, status=0/SUCCESS)
   Status: "FRR Operational"
    Tasks: 13 (limit: 49244)
   Memory: 19.0M
   CGroup: /system.slice/frr.service
           ├─230731 /usr/lib/frr/watchfrr -d -F traditional zebra bgpd staticd
           ├─230749 /usr/lib/frr/zebra -d -F traditional -A 127.0.0.1 -s 90000000
           ├─230756 /usr/lib/frr/bgpd -d -F traditional -A 127.0.0.1
           └─230765 /usr/lib/frr/staticd -d -F traditional -A 127.0.0.1

Jul 22 18:31:18 sakthi-vpc-a-vsi watchfrr[230731]: staticd state -> up : connect succeeded
Jul 22 18:31:18 sakthi-vpc-a-vsi watchfrr[230731]: all daemons up, doing startup-complete notify
Jul 22 18:31:18 sakthi-vpc-a-vsi frrinit.sh[230725]: Started watchfrr
Jul 22 18:31:18 sakthi-vpc-a-vsi systemd[1]: Started FRRouting.
Jul 30 10:38:50 sakthi-vpc-a-vsi bgpd[230756]: %NOTIFICATION: received from neighbor ip 6/4 (Cease>
Jul 30 10:38:52 sakthi-vpc-a-vsi bgpd[230756]: %NOTIFICATION: sent to neighbor ip 6/7 (Cease/Conne>
Jul 30 10:38:54 sakthi-vpc-a-vsi bgpd[230756]: bgp_update_receive: rcvd End-of-RIB for IPv4 Unicast from 163.>
Jul 30 12:19:26 sakthi-vpc-a-vsi bgpd[230756]: %NOTIFICATION: received from neighbor ip 6/4 (Cease>

Running config:

sakthi-vpc-a-vsi# show running-config
Building configuration...

Current configuration:
!
frr version 7.5
frr defaults traditional
hostname sakthi-vpc-a-vsi
log file /var/log/frr/bgpd.log
log syslog informational
no ipv6 forwarding
no service integrated-vtysh-config
!
router bgp 64555
 no bgp ebgp-requires-policy
 neighbor ip remote-as 64565
 neighbor ip ebgp-multihop 255
 neighbor ip disable-connected-check
 neighbor ip update-source 10.248.64.4
 !
 address-family ipv4 unicast
  network 10.248.0.0/24
  network 10.248.64.0/24
  neighbor ip soft-reconfiguration inbound
 exit-address-family
!
ip nht resolve-via-default
!
line vty
!
end

FIB:

[root@sakthi-vpc-a-vsi ~]# ip route show
default via 10.248.64.1 dev eth0
default via 10.248.64.1 dev eth0 proto dhcp metric 100
10.248.64.0/24 dev eth0 proto kernel scope link src 10.248.64.4 metric 100

Can anyone help?

[sakthishanmugam02]

@ton31337
@riw777
would you be able to help here?

[sakthishanmugam02]

I am able to make the required changes, it works now - I configured BGP peer with public IP and then private network next hop is not resolving. Now it is able to install routes properly.

Now I see:

B>  10.249.65.0/24 [20/0] via 10.249.64.4 (recursive), weight 1, 00:00:16
  *                         via 10.248.64.1, eth0, weight 1, 00:00:16

What does that recursive mean?

[ton31337]

It means it tries to find the next-hop via default route (ip nht resolve-via-default).