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I would like to thank everyone that took time and voted on the subject of my next on-line session. We have a clear winner: Dynamic routing across a firewall … although the closeness of the other topics might indicate a helping hand of our polish friend. Unfortunately, I have some bad news to go with the good ones – the “December” session will most likely happen in January or February (I'm simply running out of time).

Dear readers! This time I really need your help (uncle Google and his relatives gave me only one relevant hit and even that doesn't work on 7200 or 1800).

I'm trying to implement an EEM applet that would detect traffic rate change using CISCO-CLASS-BASED-QOS-MIB. Everything would work perfectly ... if only IOS wouldn't update the MIB counters approximately every 10 seconds, not in real-time. Is anyone aware of a configuration command that would force the router to update these counters any faster?

The “Sometimes the path is more important than the destination” post has generated numerous highly interesting comments. I already planned to write about some of the issues raised by the readers (certification grind mill) or wrote about others (knowledge or recipes), so I’ll skip those and focus on the other interesting bits-and-pieces (but please make sure you read the original post first).

One of my readers sent me a question that triggered one of my old grudges:

In my experience, when you first add a new switch (having a NULL domain) on an existing VTP Domain, it inherits the domain name, regardless of it being a VTP Server. I was wondering if this is a feature (i.e. has proved to be a solution in most cases) or a bug (i.e. has proved to cause problems in most cases). I know it's proved to be the latter for us!

In my personal opinion Cisco at one point in time wanted too much plug-and-play and someone had a great idea that you can just plug another switch into your network and it would autoconfigure itself. We've been suffering because of that "insight" ever since (and the CCIE written test has material for a few more interesting questions :).

I strongly believe that VTP should be turned off by default and should generate a warning before being enabled, but it will probably not happen. What do you think?

Disclaimer: I am not a switching person and have no idea about anything below or above layer 3.

I was delighted when I got access to Cisco’s Application Control Engine (ACE) XML Gateway/Web Application Firewall (WAF) box. This box is the perfect intersection of three fields that really interest me: networking, security and Web programming. To my huge disappointment, though, all the real configuration can only be done through the Web interface. I understand that casual users of a device prefer a graphical user interface (GUI) over text commands (and Generation Z has never seen a terminal window, DOS prompt or, God forbid, an actual terminal), but you can achieve so much more with a simple text-based configuration approach:

This is a nice MPLS question I’ve received from one of the readers:

I have understood the Penultimate Hop Popping (PHP) process, but I don’t understand when a router would use UNTAGGED instead of POP TAG?

Instead of answering the question directly, let's walk through a series of simple Q&A pairs that will help you understand the whole process (remember: knowledge, not recipes!).

I received an interesting comment on one of my knowledge/certification-related posts:

I used to think that certifications were a useful indicator of knowledge or at least initiative, but I’m changing my mind. [...] I feel like I’ve gotten a lot out of studying for certifications, especially CCIE, but I’m starting to wonder if that’s the exception.

I guess a lot of prospective internetworking engineers are thinking along the same lines, so here’s my personal perspective on this issue.

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You might remember that the last polls I did using Blogger all resulted in every option having exactly the same number of votes. At that time, I've blamed Google ... and I have to apologize. It was obviously someone who has nothing better to do in his life. The log files I've collected indicate he's coming from Poland and I would appreciate if my Polish readers could help me persuade this troubled individual that he should spend his time doing something else (details in the rest of the post).

Just stumbled across this: Amazon is offering the MPLS and VPN Architectures, MPLS and VPN Architectures, Volume II and Internet Routing Architectures (2nd Edition) (Networking Technology) (from Sam Halabi) for a total of $160.

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I was delighted when I got access to Cisco's ACE XML Gateway/Web Application Firewall (WAF) box. This box is the perfect intersection of three fields I'm really interested in: networking, security and web programming, so I'll work with it quite a lot in the future and post interesting tips and tricks about its usage.

As this blog is currently focused exclusive on Cisco IOS, I'm wondering how to cover these new products. I won't create another blog; it simply doesn't make sense to build another blog from the ground up, but there are a few other options. Please help me select the best one by voting in the poll.

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