What qualifies as "excessive broadcasts" ?

[Søren Fisker]

I have been working with the danish HP network support on this for a while, and although they're very nice people they have no clue as to what's wrong - and thus have been completely useless.
I've tried firmware H.08.58 (not yet on web) which made no difference.
They basically tell you that it's a problem with either nic, patch cable or switch port. When you've checked those they'll offer to replace the switch, and if that doesn't help they're completely lost.
I'm very sure this is a firmware problem.

Regards,
Soren

[Les Ligetfalvy]

I have seen power management settings cause excessive port toggles. Make sure to turn off power management on the NIC.

While the following does not cause port toggles, I also like to turn off LACP on most switches and make sure that spanning tree is properly configured.

[Les Ligetfalvy]

Since upgrading my 5308 switches to 10.04 code, these FFI events that so often accompanied a link up are almost entirely eliminated. Kudos to the software engineer that fixed it. Reviewing my SysLogs is almost a pleasure now.

[Søren Fisker]

Let's hope the fix is ported to 2650/2824.
Anyway we'll hopefully be switching to 5308's soon, so this is reeeeeaaaaally good news.

Soren

[Søren Fisker]

Since it's not mentioned in the release notes (neither fix nor enhancement), it'll probably be back in the next version

:-)

[robdal]

we have a lot af 8000M switches with 100BaseFx-modules. Our PC's mostly have a 3C905B-FX NIC, but we also have many laptops with mediaconverters (100baseFX-100BaseT. (fiber all the way between swithces and computers).

I see many of these excessive messages when there is a mismatch between the duplex-settings on the NIC and the switchport. All of our switchports are set to 100FullDuplex, but sometimes the NIC's on the PC are set to hardware default, auto or 100HalfDuplex and then the log are filled up with excessive broadcast. it also happens when the mediaconverter is not correctly configured.

TIP: to filter out write "log exc".

When I visit the user to correct the NIC-settings, most of them havent noticed any slow performance. seems to me that this is only unnecessary noice in the log.

[hello007]

Excessive broadcast and multicast traffic can seriously degrade network performance. By following the configuration examples given here and disabling IP-directed broadcasts
on edge routers, it is possible to mitigate the effects of excessive broadcast and multicast traffic.

[Vince-Whirlwind]

...except these "error" messages aren't caused by "excessive" broadcasts.

I may be wrong, but I assume they are caused by PC NIC traffic being dropped by the switchport while it is in "blocking" for a period as it becomes enabled. The PC is getting no reponse to its ARPs and keeps sending requests as all the active processes become aware the NIC is up and start sending traffic to it.