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New Member

Connect existing network

Hi all

I am building a lab before I can move on to seperate our existing network (no VLAN, all devices in the same subnet)

I use 01 cisco router 2911 to connect 01 no-VLAN network with other VLANs network

They can work well if I point the default gateway of the PC belong to no-VLAN network to the IP address that I configure for Router interface.

But if I use another default gateway, they cannot work.

Because our existing no-VLAN network have a different gateway, I need to keep the existing configuration (no change). How can I configure the router to receive all packets from the existing no-VLAN net work? (without changing the default gateway of that network)

What I did:

PC  <---->   existing no-VLAN network  (gateway: 172.x.x.4)   <------>  router (ip interface G 0/1:

If I changed gateway in PC from 172.x.x.4 to ===> it works

but I do not want to change this gateway

Please help


New Member

Connect existing network

Sorry, I am a little confused on the issue, but it sounds like you need to add an IP ROUTE statement. Basically telling everything to route to .102 unless it's Internet Traffic.

Sorry, I you might need to explain it a little bit better.

New Member

Re: Connect existing network


I meant that our existing network is NON-VLAN (172.x.x.x) with all users and servers in the same network.

I want to seperate users by build new networks with several VLANs.

Now I use router Cisco 2911 to connect our existing network with the new VLANs.

The problem is our existing network has it own gateway (172.x.x.4). And I configured in router Cisco another IP address ( ==> I connected the existing network to this interface. Howerver, to make the existing network works, I have to change the IP default gateway for my PC from 172.x.x.4 to

This is a lab, so in real existing network I cannot change the IP default gateway like that. I need to keep all things the same

What should I configure in the router ?


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