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Connection a managed Cisco 3825 router to our own Cisco3640

gentleben asked
Medium Priority
Last Modified: 2012-05-06
I work at a WISP and we switched providers who installed a managed Cisco 3825 series router with a 12 meg connection until they can run our DS3 circuit. I have been given a 12.x /23 block of addresses with this. At present all my wireless access points use our Cisco 3640 router as their gateways. These are all on 10.x subnets so we can manage the antennas from here.
 I broke the /23 into two /24 networks. I applied one of the new public Ip addresses to int FE0/0 on the 3640 12.x.x.253 and natted it outside. The two routers are both plugged into the same Cisco 2950 switch. So my default route 12.x .x.254 a secondary address on the managed 3825 router.  Is this setup ok? We seem to be slow. I am wondering if I need to just connect the FE0/0 straight to the 3825 Lan port?  All of my routing is static by the way on the 3640.As you can see I am confused. Of cource I am having dns issues at the same time which is a whole other area.  Thanks for your help.
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Top Expert 2009
Sounds like you have it right.  The switch between the two routers is fine.  Verify the port stats on the switch for the ethernet interfaces from the two routers.  Make sure there are no input errors.  Are you running auto/auto on the router and switch port or do you have them set to 100/Full on all ports?  The DNS issue itself could be the cause of the slowness.

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