Lab: GRE Backup Interface

Hi, I'm having trouble when running the ping command over the backup interface on Tunnel 45. I can successfully get the backup interface to come up. I am using VIRL with sub-interfaces. I don't have the same output as the workbook does. The route to 150.1.5.5 is installed in the FIB, however, the ping fails and I'm unsure why. Can you please take a look at the output below. I'm running an "debug ip packet" on R4 and R5. 

 

R4#sh ip route static | b Gateway

Gateway of last resort is not set

 

      150.1.0.0/32 is subnetted, 2 subnets

S        150.1.5.5 is directly connected, Tunnel45

 

R4#ping 150.1.5.5 repeat 1 source lo0

Type escape sequence to abort.

Sending 1, 100-byte ICMP Echos to 150.1.5.5, timeout is 2 seconds:

Packet sent with a source address of 150.1.4.4 

 

*Feb  6 21:29:28.083: IP: s=150.1.4.4 (local), d=150.1.5.5 (Tunnel45), len 100, sending

*Feb  6 21:29:28.083: IP: s=150.1.4.4 (local), d=150.1.5.5 (Tunnel45), len 100, sending full packet.

Success rate is 0 percent (0/1)

 

R5#

*Feb  6 21:29:28.537: IP: s=155.1.45.4 (GigabitEthernet0/1.45), d=155.1.45.5, len 124, enqueue feature, TCP Adjust MSS(5), rtype 0, forus FALSE, sendself FALSE, mtu 0, fwdchk FALSE

R5#

 

Now here is when the ping actually works when Tunnel 100 is enabled. 

R4#ping 150.1.5.5 source l0 repeat 1

Type escape sequence to abort.

Sending 1, 100-byte ICMP Echos to 150.1.5.5, timeout is 2 seconds:

Packet sent with a source address of 150.1.4.4 

!

Success rate is 100 percent (1/1), round-trip min/avg/max = 1/1/1 ms

R4#

*Feb  6 21:43:48.722: IP: s=150.1.4.4 (local), d=150.1.5.5 (Tunnel100), len 100, sending

*Feb  6 21:43:48.722: IP: s=150.1.4.4 (local), d=150.1.5.5 (Tunnel100), len 100, sending full packet

*Feb  6 21:43:48.723: IP: s=169.254.100.5 (GigabitEthernet0/1.100), d=169.254.100.4, len 124, enqueue feature, TCP Adjust MSS(5), rtype 0, forus FALSE, sendself FALSE, mtu 0, fwdchk FALSE

*Feb  6 21:43:48.723: IP: s=150.1.5.5 (Tunnel100), d=150.1.4.4, len 100, input feature, MCI Check(109), rtype 0, forus FALSE, sendself FALSE, mtu 0, fwdchk FALSE

*Feb  6 21:43:48.723: IP: s=150.1.5.5 (Tunnel100), d=150.1.4.4, len 100, rcvd 4

*Feb  6 21:43:48.723: IP: s=150.1.5.5 (Tunnel100), d=150.1.4.4

R4#, len 100, enqueue feature, TCP Adjust MSS(5), rtype 0, forus FALSE, sendself FALSE, mtu 0, fwdchk FALSE

R4#

*Feb  6 21:44:00.883: IP: s=169.254.100.4 (local), d=169.254.100.5 (GigabitEthernet0/1.100), g=169.254.100.5, len 200, forward

 

R5#debug ip packet

IP packet debugging is on

R5#

*Feb  6 21:43:49.220: IP: s=169.254.100.4 (GigabitEthernet0/1.100), d=169.254.100.5, len 124, enqueue feature, TCP Adjust MSS(5), rtype 0, forus FALSE, sendself FALSE, mtu 0, fwdchk FALSE

*Feb  6 21:43:49.221: IP: s=150.1.4.4 (Tunnel100), d=150.1.5.5, len 100, enqueue feature, TCP Adjust MSS(5), rtype 0, forus FALSE, sendself FALSE, mtu 0, fwdchk FALSE

 

Is this a bug? 

ps. I've also left this feedback in the workbooks themselves. 

Thank you!

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