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Is it possible to split a Network into 2 parts? Example there are a Network i want to split one Address, the last one for example, to a diffrent vlan. So can i create IP based VLANs? Is it possible or i need a router for this function?

Something like

vlan1: - on port 1 & 2 
vlan2: - on port 1 
vlan3: on port 2

Any suggestion?

Regards Rene

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up vote 2 down vote accepted

You can't really split off the subnet like you're thinking without creating two new subnets of and

What you may be looking for is an ACL on the ports?

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I think i did not need vlan but a ACL that allow only Address on Port 3, Port 1 deliver the IPs and Port 2 can access the wohle IP Range. – kockiren Mar 24 '11 at 12:46
Yes, you need an ACL. Something like: allow, deny any. – Hyppy Mar 24 '11 at 12:50
So i access to Port 3 with "int fa0/3" but i can only set ip address and ip igmp is'nt ACL supported on Catalyst 2950? – kockiren Mar 24 '11 at 13:56
The configuration guide for 2950 ACLs is available here:… – Hyppy Mar 24 '11 at 14:00
thx. I setting up an ACL with number 101 but how can i assign this ACL to Port 3? I can't find anything in the Docu?! – kockiren Mar 24 '11 at 14:44

You're misunderstanding VLAN's and subnetting.

A port can only belong to one VLAN unless it's a trunk port.

You can't assign the same ip address range to each VLAN. Well, you can but network communication won't operate properly as you won't be able to route traffic from one VLAN to another as they're all in the same subnet.

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I have 3 Ports, one came from Router with Addresses to Port1, on Port 2 there are a firewall they use Addresses .130-.189 and to Port3 there are only .190 Address. So i did not need a vlan but a restriction that Port 3 only Access with .190 Source-IP. It is possible? – kockiren Mar 24 '11 at 12:45

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