Steps:

1. Create 2 networks(NET1, NET2)
2. Create dual stack subnets(1 for IPV4, 1 for IPV6) on bot the networks.
3. Create custom security group, allow all IPV4 and IPV6 rules.
4. create 4 ports, 2 for each network on 2 DPNs with allowed address pair as the extra route IPs(In this case, 76.1.1.2 and 77.1.1.2)
5. Create a router and attach both the subnets to the router.
6. spawn 4 VMs on 4 ports.
7. configure extra route IP for the interface eth0:1, eth0:2 for both extra routes.
8. Update the router with the extra routes.
9. Login to the other VM from the same network, and try to ping the VM where the extra route is configured.

Actual result:

IPV4 ping should work.

Expected result:

IPV4 ping is not working

NOTE: Same issue is seen for IPV6 ping as well.

Investigations:

======================================================

• eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
  inet 30.1.1.3 netmask 255.255.255.0 broadcast 30.1.1.255
  inet6 fe80::f816:3eff:feb2:b8fb prefixlen 64 scopeid 0x20<link>
  inet6 2001:db5:0:2:f816:3eff:feb2:b8fb prefixlen 64 scopeid 0x0<global>
  ether fa:16:3e:b2:b8:fb txqueuelen 1000 (Ethernet)
  RX packets 153 bytes 17178 (16.7 KiB)
  RX errors 0 dropped 116 overruns 0 frame 0
  TX packets 31 bytes 2826 (2.7 KiB)
  TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

eth0:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 76.1.1.2 netmask 255.255.255.0 broadcast 76.1.1.255
ether fa:16:3e:b2:b8:fb txqueuelen 1000 (Ethernet)

eth0:2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 77.1.1.2 netmask 255.255.255.0 broadcast 77.1.1.255
ether fa:16:3e:b2:b8:fb txqueuelen 1000 (Ethernet)

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 0 (Local Loopback)
RX packets 18 bytes 1692 (1.6 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 18 bytes 1692 (1.6 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
 

• RD Prefix NextHop Label Origin
  -------------------------------------------------------------------
  ac87de59-b40a-438b-950f-403c1718d5d0 40.1.1.3/32 192.168.113.10 103025 l
  ac87de59-b40a-438b-950f-403c1718d5d0 30.1.1.3/32 192.168.113.10 103017 l
  ac87de59-b40a-438b-950f-403c1718d5d0 40.1.1.1/32 0.0.0.0 103023 l
  ac87de59-b40a-438b-950f-403c1718d5d0 2001:db5:0:2:f816:3eff:feb2:b8fb/128 192.168.113.10 103016 l
  ac87de59-b40a-438b-950f-403c1718d5d0 30.1.1.4/32 192.168.113.11 103019 l
  ac87de59-b40a-438b-950f-403c1718d5d0 30.1.1.1/32 0.0.0.0 103004 l
  ac87de59-b40a-438b-950f-403c1718d5d0 40.1.1.4/32 192.168.113.11 103024 l
  ac87de59-b40a-438b-950f-403c1718d5d0 76.1.1.0/24 192.168.113.10 103026 s
  ac87de59-b40a-438b-950f-403c1718d5d0 2001:db5:0:3:f816:3eff:fecd:4175/128 192.168.113.10 103021 l
  ac87de59-b40a-438b-950f-403c1718d5d0 2001:db5:0:2:f816:3eff:feea:4f4a/128 192.168.113.11 103018 l
  ac87de59-b40a-438b-950f-403c1718d5d0 77.1.1.0/24 192.168.113.10 103027 s
  ac87de59-b40a-438b-950f-403c1718d5d0 2001:db5:0:3:f816:3eff:fe3c:1a17/128 192.168.113.11 103022 l
  ac87de59-b40a-438b-950f-403c1718d5d0 2001:db5:0:2::1/128 0.0.0.0 103001 l
  ac87de59-b40a-438b-950f-403c1718d5d0 2001:db5:0:3::1/128 0.0.0.0 103020 l
   

• cookie=0x8000003, duration=472.789s, table=21, n_packets=0, n_bytes=0, priority=34,ip,metadata=0x324b0/0xfffffe,nw_dst=76.1.1.0/24 actions=group:152516
  cookie=0x8000003, duration=472.742s, table=21, n_packets=0, n_bytes=0, priority=34,ip,metadata=0x324b0/0xfffffe,nw_dst=77.1.1.0/24 actions=group:152518

Extra route IPs are not seen in table 21 on the DPN2 side.

Please refer the attached file for the datastores