Flooded Packets on 450 - Normal?

[simonspivey]

Anyone know what % of packets should be 'flooded' packets?

I have just installed 2 450s (linked thru UTP for now), 1 has single 400-FX link to Accelar 1100. Flooded packet count increments fairly steadily on this port, about 1% of total RX packet count. Didn't notice this before.

Other counts are OK- zero or nominal. UTP link ports look OK too.
Thanks,
Si.

 

[jimbopalmer]

As I under stand it, you Flood packets when you have no idea where a MAC address is. So if most of the network is toward the Accelar 1100, while the other ports are single devices, it would make most sense if the only device flooding the 450 was the 1100, looking for MAC addresses it did not know.

Mind you, that is just my vision of the process, my usual sources of flooded and filtered packets are 10 mbps hubs, which simply don't know any better. Perhaps someone can do better.

I tried to remain child-like, all I acheived was childish.

 

[niklasw]

yeah, what jimbo said!

Err, just one question, where do you find this info bout the flooding? In Device Manager? A bit more specifics would help in trying to help you

-Cheers, Niklas

 

[jimbopalmer]

I telnet into my switches, as I am old school, but I bet JDM has the same stats, some where.



I tried to remain child-like, all I acheived was childish.

 

[simonspivey]

I go in through Telnet (or for some other stats, direct GET query). I noticed that through the Accelar device manager, there is no 'flooded packets' stats. Rarely use TELNET on the Accelar though--totally different UI.

I think I have satisfied myself that there was nothing wrong with the switch performance, though the TELNET interface seems really sluggish on both switches (lags behind keystrokes). My existing 350s don't seem to have this problem...

Si.
Lakefield College School

 

[anthonyanderberg]

Its worth pointing out that the layer-2 forwarding databases have a timeout value (5 minutes I think), so most mac addresses will lapse into an 'unknown' state a few times a day if they are quiet for more than the timeout period.