Excessive Broadcast Problem with Procurve 2626

[GuiGui_1]

Hi,

I've a problem with my enterprise switch HP Procurve 2626.

When I plug on 2626's ethernet port a basic hub (8 slots, per example), and when I do a boucle on this simple hub (plug 2 ports with one ethernet cable), the Procurve 2626 literaly panic.

Ping up to 1ms< to 50ms and after some minutes, it doesn't respond...

RSTP on 2626 is active, and Broadcast-limit is set (i tried with 1 to 50).
Fault-finder is set to Hight too...

Well, what can i do for 2626 disable the port who the Hub is plug, when there's a broadcast problem on it ?

Regards,

[Matt Hobbs]

What firmware revision are you running? Since H.08.62 spanning-tree should be able to detect external loops and block them.

Is this other device a hub or a switch? Some switches do not forward BPDU packets, in this case the updated firmware will not help and you need a 'loop protect' feature. I believe the 2600 series will be coming out with this in the not too distant future.

[GuiGui_1]

My version is h.10.29

Loop-detection is enable on all port, action is send-disable, but nothing append on the problematic port...

The device which do the loop are an HUB, a simple public hub.

Then, you try to tell me that the 2626 can't detect the hub loop ?

If 2626 can't disable the port where hub is plug, what model of HP can do this ? 2848 ?

Thanks for answer =)

[GuiGui_1]

Other point, i think ur write and the little HUB don't forward the BPDU packet, but 2626's detect this traffic has non-unicast traffic.
But it doesn't block it...

If no BPDU is send, what is the solution ? -_-'

[GuiGui_1]

Ok then,

I do this command :
2626(config)# spanning-tree ethernet 1-24 mcheck bpdu-protection

And immediatly the port where the hub is connect becomme in bpduError state...

But, i've not exaclty understand what does this command...

Can you explain this ?

Best regards :)

[GuiGui_1]

Well, i'd understand what the previous command do...
But, now the problem he's solve, but i can't plug any switch on the 2626 (i define the mcheck bpdu-protection on all port except the fiber port)...

Another idea ?

[Matt Hobbs]

My mistake, I didn't realise H.10.29 was out which does include the loop protect feature. (but is not documented). Your device does seem to be forwarding BPDU's as it has gone into BPDUerror which should have disabled the port.

It is interesting though that with spanning-tree only enabled it did not 'block' that port.

[GuiGui_1]

Ok, after test, everything is OK, but i've a last question (i promess =) ), if i plug a switch on the 2626, it gonna down the port where i plug it ?

And, how can i up a BPDUError port ?
The only solution i find is :
(config)#no span-tree mcheck PORT bpdu-protection

And for up :
(config)#span-tree mcheck PORT bpdu-protection

Ty a lots :)

[Matt Hobbs · Accepted solution]

To get out of BPDUerror, you can go into the interface and re-enable it.

2600(config)# int 25
2600(eth-25)# enable

Or you can set a timer so that it will automatically try and re-enable it:

2600(config)# spanning-tree bpdu-protection-timeout

You can also set a timeout for the loop-protect feature.

loop-protect is probably slightly more powerful in that it can prevent a broadcast storm caused by a switch that does not forward BPDU's.

I just tested out both features on my 2600 and they seem to be working as designed so far.

[GuiGui_1]

I tried loop-protect but it seem's to not working for my problem.

What conf you do exactly ?

Ps : Thx for timer tips :)