I am an intermediate, not professional network admin for my own small business. I am attempting to add a new tunnel interface for a new VPN branch. I'm using the same config I have implements many times before - this will be my 4th branch. However I'm running into this error message I can't resolve myself. Here is the text from the commit error...

"In virtual-router default: address on interface vlan.2 is duplicate with address on interface ethernet1/1.(Module: routed) Commit failed"

Which seems to have nothing to do with the new tunnel I am adding, which will be a network on Ethernet 1/1 is my wan connection, which is gets a dhcp ip address from my isp, and has no interface ip address specified. My vlan serves addresses on network

In my own troubleshooting, it seems that if I make any change at all to my virtual router config, commits will fail with this error.

I'm lost, I've searched my config and cannot find what it is referring too. Any ideas what's up?

I really appreciate the assistance!

  • 2
    Your subnets and are overlapping. That's why you can't commit.
    – user36472
    Jun 1, 2017 at 5:50
  • Thank you for your reply. I have checked over everything and I can not find a subnet defined anywhere. It's like... it's a glitch :| I even exported the config and searched the entire thing for that ip address, and the only reference is a static ip assignment in my virtual router. Not as a subnet, just the ip. I don't understand what it's referencing. Jun 1, 2017 at 6:17
  • As i undertand Ethernet1/1 is DHCP? If your ISP delivers the address on Ethernet1/1 via DHCP it will be overlapping.
    – user36472
    Jun 1, 2017 at 13:40
  • Thanks again, Crown! The ISP is Comcast and the address they are issuing is in a different subnet.... I'm not sure where it's getting the idea that 192.168.100.x is related to Ethernet1/1 at all haha Jun 1, 2017 at 13:46
  • Can you log into the command line and post the output from the command "show interfaces all"
    – John K.
    Jun 1, 2017 at 15:12

1 Answer 1


Wanted to update with how I resolved this. Basically something apparently got corrupted in the config files. The behavior started when I was trying to add a new tunnel interface, but initially would disappear when I reverted to one of my saved configs. After a while even this action would not resolve the error (same one noted above). So - I reverted to factory! Needless to say that is less than ideal, I'm very surprised to have this type of issue with this box. Once I did so I was able to import my saved configuration file and add the tunnel interface with no errors.

  • You should post your resolution in your answer, then accept your answer. Without an accepted answer, the question will keep popping up forever, looking for an answer.
    – Ron Maupin
    Jun 3, 2017 at 0:03

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