multiple interfaces on the same subnet and Vlan

[rjmeredeth_DUP]

Does anyone know if it is possible to add a second IP interface in the same vlan and subnet. The reason being.. I have an old router that has functioned as the default gateway for my network for years. I have brought up a new router in parallel and have migrated most of my network to the new default gateway. I want to remove the old router from the network, but I would like to move the ip address to the new router so i don't break anything I may have missed. Is there any way to do this? This is on a 6850 with current code (6.3.1.1052).

Thanks,
Robb

[Rens_DUP]

Hello Robb,

Yes you can. I haven't used it before but you can quite easy assing multiple ip addresses to the same VLAN.

Code: Select all

ip interface "interface200" address 192.168.200.254 mask 255.255.255.0 vlan 200
ip interface "interface230" address 192.168.230.254 mask 255.255.255.0 vlan 200

This creates to interfaces interface200 and interface230 both assigned to the same VLAN.

Regards,

Rens

[rjmeredeth_DUP]

Rens, thanks for your response. Unfortunately, I already tried that. it gives:

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-> ip interface "test1" address 172.16.150.65 mask 255.255.0.0 vlan 3
-> ip interface "test2" address 172.16.155.65 mask 255.255.0.0 vlan 3
ERROR: Ip Address must not conflict with interface test1

[rjmeredeth_DUP]

I think I've figured it out.

Code: Select all

vlan 100
ip interface "test1" address 172.16.0.1 mask 255.255.0.0 vlan 100
vrrp 1 100
vrrp 1 100 address 172.16.0.2
vrrp 1 100 enable

I don't know if that is the best way to do it, but it seems to work.

[benny]

You can't have two IP interfaces from the same subnet. VRRP is a valid way to solve that "issue" ...

-benny