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Community Member

New Subnet


I have a subnet of 192.149.1.x/24 and have run out of IPs. So I want to put up an additional subnet of 10.1.23.x/24 so that all the machines can communicate with one another. I have been told by a friend to put up a small 2-port Cisco router. Will it solve my problem? I am giving the sketch of out LAN below:

T1 Line--Router--Firewall-cum-Gateway--Switch--LAN/Internal machines

Where should I put the router and what entries do I have to make on that?

An early response would be highly appreciated.

Thanks in advance,


Community Member

Re: New Subnet

That would work, with the router connected to the switch(s) If you only have one switch, you will need

to do vlans. Another (labor intensive) option is to

re-address the internal machines to network 10, and give yourself a larger mask.

Community Member

Re: New Subnet

Can the router you have do secondary IP? If it's a Cisco the answer is more likley to be Yes. The idea is to have two ip addresses on one interface. You could have your 192.x.x.x and the 10.1.23.x on the same router interface.

Cisco config, looks like this:

Interface FastEthernet 0

IP Address

IP Address Secondary

With this in place the host on the 192 and 10 network will be using the same router's ethernet interface as a gateway. The router will handle all the communications between the 192 & 10 network also.

Done it may times, too many times. It's not pretty or a long term solution, but it works.

When you go to doing thing like this you are more likley to have other problems later on. For instance broadcast problems, too many nodes on one broadcast domain. Also a router will have to handle the communication between two computers that are in the same broadcast domain which adds latency.

Hope this helps....

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