VIRL Simulation – L3 connectivity Usecase

Networking & SDN, ,

This is a continuation of my VIRL, CML blog series. VIRL/CML overview is covered here. Here, we will create a L3 IGP network running OSPF. I have used IOS nodes for all routers, we can use XR and NXOS routers as well. I didnt do it because the VM images are bigger for XR and NXOS and it slows up the simulation.

Following is the Network topology I created during the design phase. iosv[1-3] are in area 0, iosv[4-5] are in area 1, iosv[6-7] are in area 3, iosv[8-9] are in area 2.

virl7

After creating the configuration, following is the OSPF topology seen in visualization phase. The different areas are shaded differently.

virl8

After starting the simulation, I was able to login to consoles of routers and servers. Servers are VMs running Ubuntu. Username and password for servers are “cisco”. Enable password for routers are “cisco”.

Lets look at OSPF outputs in iosv-1. We can see that OSPF has converged and all the routes are seen.

iosv-1#show ip ospf neighbor 

Neighbor ID     Pri   State           Dead Time   Address         Interface
192.168.0.5       1   FULL/DR         00:00:36    10.0.0.10       GigabitEthernet0/2
192.168.0.4       1   FULL/DR         00:00:34    10.0.0.6        GigabitEthernet0/1
192.168.0.8       1   FULL/DR         00:00:36    10.0.0.22       GigabitEthernet0/3
192.168.0.11      1   FULL/DR         00:00:39    10.0.0.26       GigabitEthernet0/4

iosv-1#show ip route ospf 
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area 
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
       a - application route
       + - replicated route, % - next hop override

Gateway of last resort is not set

      10.0.0.0/8 is variably subnetted, 24 subnets, 3 masks
O        10.0.0.12/30 [110/3] via 10.0.0.22, 01:29:56, GigabitEthernet0/3
O        10.0.0.16/30 [110/2] via 10.0.0.22, 01:29:56, GigabitEthernet0/3
O        10.0.0.28/30 [110/2] via 10.0.0.10, 01:29:56, GigabitEthernet0/2
                      [110/2] via 10.0.0.6, 01:29:46, GigabitEthernet0/1
O        10.0.0.32/30 [110/3] via 10.0.0.22, 01:29:56, GigabitEthernet0/3
O IA     10.0.0.36/30 [110/2] via 10.0.0.6, 01:29:46, GigabitEthernet0/1
O        10.0.0.40/30 [110/2] via 10.0.0.26, 01:29:56, GigabitEthernet0/4
O        10.0.0.44/30 [110/3] via 10.0.0.26, 01:29:56, GigabitEthernet0/4
O IA     10.0.0.48/30 [110/3] via 10.0.0.6, 01:29:46, GigabitEthernet0/1
O IA     10.0.0.52/30 [110/2] via 10.0.0.10, 01:29:56, GigabitEthernet0/2
O IA     10.0.0.56/30 [110/3] via 10.0.0.10, 01:29:56, GigabitEthernet0/2
O        10.0.0.60/30 [110/3] via 10.0.0.26, 01:29:56, GigabitEthernet0/4
O        10.0.0.64/30 [110/2] via 10.0.0.22, 01:29:56, GigabitEthernet0/3
O IA     10.0.0.68/30 [110/3] via 10.0.0.10, 01:29:56, GigabitEthernet0/2
                      [110/3] via 10.0.0.6, 01:29:46, GigabitEthernet0/1
O        10.0.0.72/30 [110/2] via 10.0.0.26, 01:29:56, GigabitEthernet0/4
      192.168.0.0/32 is subnetted, 9 subnets
O        192.168.0.4 [110/2] via 10.0.0.6, 01:29:46, GigabitEthernet0/1
O        192.168.0.5 [110/2] via 10.0.0.10, 01:29:56, GigabitEthernet0/2
O        192.168.0.7 [110/3] via 10.0.0.22, 01:29:56, GigabitEthernet0/3
O        192.168.0.8 [110/2] via 10.0.0.22, 01:29:56, GigabitEthernet0/3
O IA     192.168.0.9 [110/3] via 10.0.0.6, 01:29:46, GigabitEthernet0/1
O IA     192.168.0.10 [110/3] via 10.0.0.10, 01:29:56, GigabitEthernet0/2
O        192.168.0.11 [110/2] via 10.0.0.26, 01:29:56, GigabitEthernet0/4
O        192.168.0.12 [110/3] via 10.0.0.26, 01:29:56, GigabitEthernet0/4

I was able to ping from server 1 to server 2 and server 3.

cisco@server-1:~$ ifconfig
eth0      Link encap:Ethernet  HWaddr fa:16:3e:16:b8:2d  
          inet addr:10.255.0.51  Bcast:10.255.255.255  Mask:255.255.0.0
          inet6 addr: fe80::f816:3eff:fe16:b82d/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1346 errors:0 dropped:5 overruns:0 frame:0
          TX packets:104 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:376317 (376.3 KB)  TX bytes:9038 (9.0 KB)

eth1      Link encap:Ethernet  HWaddr fa:16:3e:cd:66:af  
          inet addr:10.0.0.14  Bcast:10.0.0.15  Mask:255.255.255.252
          inet6 addr: fe80::f816:3eff:fecd:66af/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:894 errors:0 dropped:135 overruns:0 frame:0
          TX packets:7 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:112941 (112.9 KB)  TX bytes:578 (578.0 B)

eth2      Link encap:Ethernet  HWaddr fa:16:3e:fc:1b:71  
          inet addr:10.0.0.18  Bcast:10.0.0.19  Mask:255.255.255.252
          inet6 addr: fe80::f816:3eff:fefc:1b71/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:923 errors:0 dropped:138 overruns:0 frame:0
          TX packets:27 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:116069 (116.0 KB)  TX bytes:2230 (2.2 KB)

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

cisco@server-1:~$ ping -c1 10.255.0.49
PING 10.255.0.49 (10.255.0.49) 56(84) bytes of data.
64 bytes from 10.255.0.49: icmp_seq=1 ttl=64 time=4.53 ms

--- 10.255.0.49 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 4.530/4.530/4.530/0.000 ms
cisco@server-1:~$ ping -c1 10.255.0.50
PING 10.255.0.50 (10.255.0.50) 56(84) bytes of data.
64 bytes from 10.255.0.50: icmp_seq=1 ttl=64 time=2.02 ms

--- 10.255.0.50 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 2.023/2.023/2.023/0.000 ms
cisco@server-1:~$ ping -c1 10.0.0.58
PING 10.0.0.58 (10.0.0.58) 56(84) bytes of data.
64 bytes from 10.0.0.58: icmp_seq=1 ttl=60 time=32.3 ms

--- 10.0.0.58 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 32.325/32.325/32.325/0.000 ms
cisco@server-1:~$ ping -c1 10.0.0.46
PING 10.0.0.46 (10.0.0.46) 56(84) bytes of data.
64 bytes from 10.0.0.46: icmp_seq=1 ttl=60 time=122 ms

--- 10.0.0.46 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 122.463/122.463/122.463/0.000 ms

Leave a comment