Problem with connection in a network.

Kinai2008 · ‎03-13-2009

Hi.

I have a network connected to two Switches, and each Switch connected to the same two Routers. Those are the gateway to the outside.

There isn't any routing protocol configured in the routers, only static routes. The interface of the routers connected to the internal network have two ips (Primary and Secondary).

The problem is that, sometimes, mainly with virtual interfaces, when we reset a PC, the router didn't detect it, until we tried to go outside. For example making a ping to the router.

Could anyone help me??

Rony Ahmed · ‎03-13-2009

I think that is normal behavior. Routers are not supposed to detect everything in the Layer 2 network. When you need to reach the gateways thats when the communication with the router happens. What is you virutal interface for? HSRP?

Rony Ahmed · ‎03-13-2009

I think that is normal behavior. Routers are not supposed to detect everything in the Layer 2 network. When you need to reach the gateways thats when the communication with the router happens. What is you virutal interface for? HSRP?

adamclarkuk_2 · ‎03-13-2009

Hi

If you mean by 'detect it' you are talking about ARP entries, then Rony is right, this is completely normal. When your PC needs to connect to the IP of the router for internet access or the router needs to send a packet to the PC, it will look in it's ARP table to see if it has a match, if not it will broadcast an ARP request onto the local subnet. The router will see this request, update it's ARP table and replay. The PC will then update it's ARP and comms will continue.

Kinai2008 · ‎03-13-2009

Ok.

I am going to try to explain it better.

When the PC want to go out it is as you said, but when the router is the one that needs to reach the PC and it hasn't a match in the ARP table, there is sometimes that the router doesn't find the PC. I don't know if it is because the router doesn't send the ARP request or the PC doesn't answer it.

Thanks for your help.