From: Darby Weaver (darbyweaver@yahoo.com)
Date: Sun Dec 17 2006 - 17:30:59 ART
Yep -
I had the unlucky experience of bringing down the
house and watching my vlans disappear one by one once
and yes, I did use the md5 password...
Even on my new 2950 switch... Yet my 4515 Sup blade
believed it anyway...
Live and learn.
--- loc.pham@comcast.net wrote:
> George,
> That is exactly why Cisco want to test all
> candidate with STP on multiple switches !!!
> Read this link will show you :
> http://www.cisco.com/warp/public/473/21.html
>
> That is also why CCIE pay big $$$ ( hopefully
> still for along time )
> HTH,
> lP
>
>
> Re: Prediction - Lab Results CCIE
> ---------------Reply to sender to list
> # From: "CCIE" <ccie@madisonsolutions.net>
> # To: "Darby Weaver" <darbyweaver@yahoo.com>,
> "'Cisco certification'" <ccielab@groupstudy.com>
> # Subject: Re: Prediction - Lab Results
> # Date: Sun, 17 Dec 2006 09:02:39 -0500
> # References:
> <923158.70406.qm@web56814.mail.re3.yahoo.com>
> # Reply-to: "CCIE" <ccie@madisonsolutions.net>
>
>
> Good morning:
>
> I concur, change is disruptive for a short period.
> Playing with four
> switches in my own lab I have started to see things
> I did not expect and
> wanted to pass along.
>
> We all have read about VTP and when you add a new
> switch to a network you
> should set the VTP to transitive before bringing the
> switch on line. The
> other day as I added a switch into my lab to
> practice spanning-tree, and the
> VTP election of the additional switch deleated all
> of my VLAN's.
>
> Having never seen this in a real network I was taken
> back for a moment. All
> of the interfaces with assigned VLAN's went from
> happy blinking green to
> flatline orange. My network went from working to
> dead.. All of the VLAN's
> that I had built were still on the interfaces but
> not in the vlan database.
>
> I discoverd the issue after a moment and resolved
> the VTP election by having
> only one "vtp mode server" in the switch domain. I
> mention this as an
> example of what can go wrong on the new lab, or
> worse what is designed into
> the new lab. With both 3550's and 3560's it would be
> very easy for the
> network to go dark in the middle of your lab because
> of a VTP issue.
>
> For the Lab I think it is wise to not only look at
> configuration issues, but
> to remember the simple rules to stop spanning-tree
> loops, check what you are
> doing as you bring up interfaces, vtp issues, etc.
> The big clue that I
> expect to see on the Lab, is that the trunking
> interfaces between switches
> are shutdown.
>
> Any port that is dark that needs be turned up is
> going to be suppect, and
> should be analized before turning up. The second
> clue would be to watch to
> see the VTP commands, and the order in which you
> activate them. If the
> VLAN's are pre-built and the primary VTP server will
> become a switch with no
> VLAN's; what have you added to your lab panic time?
>
> The last tip before I go to breakfast, study the
> switch topology before
> starting to configure the swith network. Expect all
> sorts of loops,
> mis-configured interfaces, etc.
>
> Merry Christmas and be loop free in 2007.
>
> George Morton, Ph. D.
> ----- Original Message ----- From: "Darby Weaver"
> <darbyweaver@yahoo.com>
> To: "'Cisco certification'" <ccielab@groupstudy.com>
> Sent: Saturday, December 16, 2006 12:43 PM
> Subject: Prediction - Lab Results
>
>
> I know that there have only been a very few
> people who
> have passed the lab since the 3-4 switches were
> introduced into the lab this last month or so...
>
> It seems it is always this way after a change,
> no
> matter how minor.
>
> However, I want to be the first to say that I
> predict
> that Lab Candidates will begin to pass the lab
> again
> at or near the same passing rates as before (the
> new
> labs were introduced last month)as early say...
> within 30 days or so.
>
> I just have a gut feeling... about this.
>
> Anyone care to watch the numbers with me...
>
> Funny how it is all a numbers game in the end.
>
> Merry Christmas and Happy New Year!
>
>
> And I can't wait till my favorite vendors update
> their
> materials on Switching as well. Not that what
> they
> have is not pretty good already, but I'm sure
> they are
> not sleeping at the wheel either.
>
>
> Meanwhile, has anyone taken a look a Cisco Press
> Practical Studies for Switching.
>
> It offers a lot of great insight if you can look
> past
> the model numbers and get the same great results
> from
> some 3550/3560's.
>
>
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