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Jffishbones

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Cisco 3550 smi routing


Hello

Looking for some configuration tips on a couple of 3550 smi switches. I currently have production PLC and PC devices on the switches and am looking to segment them into 2 networks but they need to talk between a single server. I have been looking at Ciscos configurations and was wondering if anyone can tell me if I have to put an IP address at each interface or just the vlan them interface belongs to? Any other tips would be appreciated. since the switches are smi they only support static and rip routing? 1 switch is running Version 12.1(13)EA1a and the other is Version 12.1(12c)EA1. In total I have 6 of the 3550 on this lan but only need to segment and route between the 2. Thanks in advance.

JF
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netspec01

You need to put an address on the VLAN interface only, not each interface.
If you sick with the standard image you will need another layer 3 device to perfrom intervlan routing.  This could be another L3 switch or a router.  Connecting a router to a switch to perform this function is called "router on a stick".  This can be done with or without trunks.  

http://www.cisco.com/en/US/products/hw/switches/ps679/products_configuration_guide_chapter09186a008007d1b7.html#39627
provides configuration examples for intervlan routing with a layer 2 switch.

Beware that router on a stick can be a performance bottleneck.  L3 switching with the enhanced image will provide the best performance.

If you upgade to the enhanced image you can do layer 3 switching:
http://www.cisco.com/warp/public/473/howto_L3_intervlanrouting.html
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JFrederick29
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I stand corrected.  The SMI version added intervlan routing starting with 12.1(11)EA1:

http://www.cisco.com/en/US/tech/tk389/tk815/technologies_configuration_example09186a008019e74e.shtml

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Is it necessary to turn on IP routing on all switches on Lan or just the 2 switches where my Vlan 4 needs to talk to Vlan 1.
Also, I do not understand the default gatewey. Devices on Vlan 1 have the router for gateway. Do I change all devices on this vlan to point to vlan IP address for gateway. And does Vlan 4 devices use Vlan 4 ip address as gateway? Thanks in advance
You can leave the VLAN 1 devices using the router for the gateway but the router will need a static route to the VLAN 4 subnet using the 3550 as the next hop.  The VLAN 4 devices should use the VLAN 4 interface IP address as their default gateway.
Thanks JFrederick29.
Jfrederick29
Thanks for the help. Everything seams to be working well for the 3550 I enabled IP routing on but I was curious, I have
another 3550 that will have ports on Vlan 4, will I need to enable routing on this switch as well or will the first 3550 handle all intervlan routing for Vlan 4 no matter what switch traffic is coming from, I did put the static route in the router to point to vlan 4.