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New Member

Subnetting an IP LAN

Inside our firewall, I use Cisco Catalyst 2924 XL and 3548 XL for our internal LAN. We use Class B private addressing on the internal LAN and only use one subnet currently. What do I have to do to add a second subnet for a particular group of PCs so that they're separate from the original subnet yet can still access the same Windows NT domain controllers for user authentication? Thank you.

  • Other Network Infrastructure Subjects
New Member

Re: Subnetting an IP LAN

You will need some sort of layer 3 device (router, routing switch, switching router) to accomodate traffic between the two subnets.


Re: Subnetting an IP LAN

You don't mention what type of firewall you use in the config but let's assume a PIX firewall. I would put the particular users in a separate VLAN, readdress the PC's, and install/connect up another NIC in the firewall and setup the firewall to allow the PC's communication to the servers on the

necessary ports/IP addresses. Under the PIX firewall documentation you should find some useful documentation even if you're not using a PIX.

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