From: Joseph Brunner (joe@affirmedsystems.com)
Date: Fri Jan 02 2009 - 22:22:11 ARST
The span will tell if the switch is looped via other internal mechanisms such as an idsm blade or nam2 blade. I have personally also seen where the nam blade can cause a loop whereby the internal forwarding of packets to and from the nam made a loop and effected traffic.
Let's do a show tac and post to the board. We'll solve!
-Joe
Sent by BlackBerry Enterprise Server
Affirmed Systems LLC
-----Original Message-----
From: asim.mz@gmail.com
Date: Sat, 3 Jan 2009 05:12:47
To: Joseph Brunner<joe@affirmedsystems.com>
Subject: Re: 6500 stp stages issue
I checked the hardware and it looks fine,
also exactly what type of info i will get from the span, it would show
me client/end points connectivity and the management is inband but why
BPDU filter will kick me off, i will appreciate if you can explain
this.
Asim
On 1/3/09, Joseph Brunner <joe@affirmedsystems.com> wrote:
> Ok, here we go to the captures;
>
> I recommend wireshark directly on the switch, with a span session for the
> offending vlan where the ports are in...
>
> Monitor session 1 source vlan x rx
> Monitor session 1 dest int g4/0/19
>
> Q. How can you easily find out if you are looped?
>
> A. Captures will show you both YOUR hostname in CDP and STP bridge priority
>
> Another trick (albeit outage causing) is simply enable BPDUGUARD globally on
> all portfast ports, and phone ports while this activity is on-going
> ***WARNING BE ON THE SWITCH VIA CONSOLE BEFORE YOU DO THIS TO AVOID GETTING
> KICKED OUT IF YOU ARE MANAGING IN-BAND****
>
> Lastly, I would check the module itself (to make sure we have no hardware
> issues)
>
> Switch#show module
>
> If you see any "error" or "unknown" I suspect hardware failure and its
> beyond us to fix that here
>
> -Joe
>
> -----Original Message-----
> From: asim.mz@gmail.com [mailto:asim.mz@gmail.com]
> Sent: Friday, January 02, 2009 6:01 PM
> To: Joseph Brunner
> Cc: Cisco certification
> Subject: Re: 6500 stp stages issue
>
> Dear Joseph,
>
> Thanks for your prompt reply,
>
> Here is the info i got from client,
>
> point 1:None of these ports are looped via cable back to each other
>
> The customer environment is huge and cannot track this but in case it
> happened how we can avoid it through some configurations as we cannot
> watch the end users all time.
>
> Point 2:Bpdufilter is NOT enabled (no spanning-tree bpdufilter enable)
>
> Yes Bpdu filter is not enabled on all switches.
>
> But what is your recommendation should not it be applied.
>
> Point 3: -if a switch or hub is connected to these ports there is no
> port on that
>> device that is looped via cable back to another port either on this switch
>> or the switching infrastructure (via another wall jack, etc.)
>
> no all the ports are connected to IP Phones or desktop clients.
>
> Asim
>
> On 1/3/09, Joseph Brunner <joe@affirmedsystems.com> wrote:
>> I suspect a bridge loop...
>>
>> Can you confirm the following
>>
>> -None of these ports are looped via cable back to each other
>> -Bpdufilter is NOT enabled (no spanning-tree bpdufilter enable)
>> -if a switch or hub is connected to these ports there is no port on that
>> device that is looped via cable back to another port either on this switch
>> or the switching infrastructure (via another wall jack, etc.)
>>
>> I fought a 6509 fire just like the one you are seeing and it was caused by
>> my third thing to check
>>
>> -Joe
>>
>> -----Original Message-----
>> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> Asim
>> Zafar
>> Sent: Friday, January 02, 2009 5:20 PM
>> To: Cisco certification
>> Subject: 6500 stp stages issue
>>
>> Dear Group,
>>
>>
>>
>> i am facing issue with some ports in 6500 causing the switch to reach
>> to 100% cpu utilization and loss the functionality,
>>
>> These ports are access ports repeatedly go from disable state to
>> forwarding state for many times and then become stable. but due the
>> transition phase the CPU utilization increase.
>>
>>
>> --
>> Thanks & Regards,
>>
>> Asim Zafar
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
>> _______________________________________________________________________
>> Subscription information may be found at:
>> http://www.groupstudy.com/list/CCIELab.html
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
> --
> Thanks & Regards,
>
> Asim Zafar
>
>
-- Thanks & Regards,Asim Zafar
Blogs and organic groups at http://www.ccie.net
This archive was generated by hypermail 2.1.4 : Sun Mar 01 2009 - 09:43:36 ARST