From: Zealist Hamamd (zealist@gmail.com)
Date: Sat Aug 09 2008 - 03:49:49 ART
Can any one mention some good links where i can find Q-in- Q tunneling in
depth.
Regards
On Sat, Aug 9, 2008 at 1:10 AM, Scott Morris <smorris@internetworkexpert.com
> wrote:
> Step back a second and think about what traffic goes where. Let's start
> with ANY broadcast or multicast traffic (don't just think IP, think which
> L2
> stuff there is) and then think about what a switch/bridge does with such
> traffic.
>
> Sends out any/all available non-receiving port. So as you trace this
> through your network, how's it look? When it comes to things like
> L2Tunneling and Q-in-Q, you are forwarding things over normally
> non-participating paths. So make sure there are no mistakes along the way
> causing stuff to be "deposited" back into a path that will cause one switch
> to re-receive a frame and therefore freak out about loopguard detection.
>
> Like I said. It's not much fun, and quite tedious to do. But a very good
> exercise in pulling one's hair out!
>
> Scott
>
> _____
>
> From: Igor Manassypov [mailto:imanassypov@rogers.com]
> Sent: Friday, August 08, 2008 3:59 PM
> To: cciestudy; 'Igor Manassypov'; 'GS CCIE-Lab'
> Cc: 'Scott Morris'
> Subject: RE: IE Lab 20
>
>
> Study,
> The stp tunnelling is for S1-S3 across S4, its got nothing to do with S2
> being shut down... l2p tunnel stp is granted to make s1-s3 share one common
> tree. I cant reason why SW2, having three trunks in parallel run to SW4 is
> being shut down. Those three are the only paths up from SW2, so honestly I
> am lost here completely.
>
> cciestudy <cciestudy@mid-world.net> wrote:
>
> From what I understand (I am not even close to an expert), is that the
> keepalive is the loop detection mechanism on the switch. Turn it off and
> the loop doesn't go away, it just doesn't detect. The STP addition was the
> fix to detect and block the loop.
>
> Scott. Correct me if I am wrong on this.
>
>
> _____
>
> From: Igor Manassypov [mailto:imanassypov@rogers.com]
> Sent: Friday, August 08, 2008 2:08 PM
> To: Igor Manassypov; cciestudy; 'GS CCIE-Lab'
> Subject: RE: IE Lab 20
>
> Besides, how does interface keepalive relate to spantree loops?
>
> Igor Manassypov <imanassypov@rogers.com> wrote:
> Hmm, whats the mechanism behind the interface keepalives that triggers the
> interface to shutdown? Besides, I really doubt that just by disabling the
> interface keepalive you avoid the loop, its just might stop going into
> errdisable but the loop will still occur if there is one (?)
>
> cciestudy <cciestudy@mid-world.net> wrote:
> I finished that lab a few weeks ago. All I can say is it was a bugger to
> solve. The IE message board has some good insight into why it was
> occurring. I believe turning off interface keep-alives resolved the looping
> problem. I believe it was SW4, F0/13, F0/15, F0/19, F0/21. Also, I tried
> doing L2protocol-tunnel on STP also...
>
>
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> Igor
> Manassypov
> Sent: Friday, August 08, 2008 9:58 AM
> To: GS CCIE-Lab
> Subject: IE Lab 20
>
> Hi Gang,
>
> Has anyone done internetwork expert's lab 20 recently? I am having a hard
> time on the first section with STP where it keeps flipping interfaces to
> err-disabled mode due to 'loopback error'. I am wondering if anyone was
> able
> to solve it.
>
> Thanks!
>
>
> Igor M., M.Eng, P.Eng
> Network Architect
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
>
>
>
>
>
>
>
>
>
> Igor M., M.Eng, P.Eng
> Network Architect
>
>
>
> Igor M., M.Eng, P.Eng
> Network Architect
>
>
>
>
> Igor M., M.Eng, P.Eng
> Network Architect
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
>
>
>
>
>
>
-- zealist@gmail.comBlogs and organic groups at http://www.ccie.net
This archive was generated by hypermail 2.1.4 : Mon Sep 01 2008 - 08:15:29 ART