MAC Aging Time & ARP

[mtornero]

Hi

I have a problem with the Aging Time Timer.

I have the following scenari:

Two routers (7300 and 7500) and their are connect to two diferent Catalyst (6500 and 4006), The 7500 router is connect to 4006 and the 7300 is connect to 6500. And these Catalyst are connect self. This is HSRP configurated and the router active is 7300. So, when a paket arrive to the 7500 router to destination to PC connect to 6500, the 4006 Catalyst do a brodcast to the all interfaces Because the MAC destination isn´t in the Catalyst 4006. When the PC response, it response to the default-gateway that is the other router, the 7300, Then, the 4006 catalyst never knowledge the MAC of this PC, Only knowledge the MAC when the router isn´t the MAC in your ARP-Table, and the router do a request ARP

I think the following:

UP the timer of Aging Time in the Catalyst and down the timer of ARP-time in the Router, then, What is the value Agin-Time and ARP-Time?

Best Regards

Miguel Tornero

[pflunkert]

Hi,

what you describe is a typical behaviour in many networks. You have Asymmetric routing between your devices. You can adjusting the MAC aging time on the respective switches to 3600 seconds (one hour) or longer.

Or you can changing the MAC aging time and ARP timeout to the same timeout value, but i would recommend a value above 3600 seconds.

Regards

Peter