I understand why Unicast flooding occurs due to asymmetric routing. But what is the BEST recommendation to deal with the issue assuming I am not going to re-architect my network.
1) Raise the bridge table timeout to 4 hours? - What are the downsides? Possibly filling the cam table?
2) Lower the arp table timeout to 5 minutes? - downside increases cpu processing on the router
I would think a compromise would be just fine as well. 10 minutes on the bridge and arp table? On a stable network arp's every 10 minutes should not be that cpu intensive.
Also, why not make the arp timer lower than the bridge timer. Than you are assured to 're-arp' before the bridge timer expires.
I am looking for some discussion on setting the timers. I have read all the links that say why this happens and to set the 2 timers to be equal. I cannot find any information on the pros and cons of messing with the timers.
This is not quite what I was looking for. Since my issue is due to Asymmetric routing I was thinking that the fix is to make both the arp and mac-address timers the same. That is what most of the documentation seems to suggests.
I don't think the mac-address-table unicast-flood command is appropriate since the flooding, be default, will occur for 3 hours and 55 minutes in every 4 hour timeframe. Maybe I am wrong but I did not think that using the mac-address-table unicast-flood command we the recommendation to resolve Unicast flooding due to Asymmetric routing. Maybe you could comment on this?
If not, than my original question still stands. What are the pros/cons of messing with the arp and mac-address-table timers and what is the most practical timer setting to use. 4 hours seems excessive to set a mac-address ageing timer to yet 5 minutes for an arp timer could prove to be very cpu intensive.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...