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alarming/monitoring broadcast storms
With broadcast storm-control enabled, you might have a broadcast storm, and not know it. Are there CLI "show" commands, SNMP traps or syslog messages which show when storm-control kicks-in? I'm especially using PowerConnect 62xx.
DELL-Willy M
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December 20th, 2012 15:00
You can view the traffic over an interface with this command.
console#show statistics ethernet 1/g1
--text omitted—
Unicast Packets Received....................... 1155457
Multicast Packets Received..................... 48339
Broadcast Packets Received..................... 76702
--text omitted—
You can get a similar view from the Web GUI Statistics/RMON=Table Views-Interface Statistics
I’m not aware of any traps that can be set.
I can look into what other possible options are available for notification.
Hope this helps,
speedcolo
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December 20th, 2012 16:00
Thanks; "show stats" doesn't tell me if a port is being throttled. I could get out a stopwatch and do a few show commands, and do some arithmetic, and if the resulting number of received broadcast packets are above my configured threshold, then I could assume that the traffic is being dropped. But unless I check frequently, or graph ifInBroadcastPkts on every port of every switch, and alarm based on that, then I would never know if/when a port is flooding.
DELL-Willy M
802 Posts
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December 21st, 2012 08:00
There are not any built in tools available that allow alarm notification for broadcast storms. The options are to use a 3rd party tool that has that has the capability to monitor the switch. Ex - Open Manage Network Manager or SolarWinds.
OMNM - www.dell.com/.../pd
speedcolo
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December 22nd, 2012 12:00
Thanks, Willy. Does OpenManage monitor ifInMcastPkts ? Or also something like ifInDiscards ?
The problem with polling "ifInMcastPkts", is that most NMS only poll at 5-minute intervals. In my case, a customer plugged-in their device with bpdufilter, created a storm (which was limited to 12kpps by Dell's default storm control), then unplugged his cable 30 seconds later. My 5-minute poller showed 1.2kpps of ifInMcastPkts over the 5 minute poll interval, which is high, but not crazy.
If there is a counter which increases during storm-control discard action (maybe ifInDiscards ?), then I could correlate a spike in input multicasts with an increase in discards in the same poll interval, and guess that storm-control kicked-in, even if only for one or two seconds.
Of course, other vendors have "storm-control action trap", but we'll work with what we can get.