Another one bites the dust – BGP+MPLS (642-691) PASSED!

It has been some time since I last updated the blog but that isn’t to say that I haven’t been working/studying away.

After finishing Internet Routing Architectures by Sam Halabi which alongside what I have learned both during my CCNP studies and whilst at my day-to-day job was going to serve as my reading to then go ahead and do the CCIP BGP exam.

Before taking the BGP exam I started reading MPLS Fundamentals by Luc D Ghein and then decided that I felt that I would be comfortable enough with both subjects to instead of taking the two separate exams (BGP & MPLS) that I would instead study and take the composite exam (BGP+MPLS, 642-691), by basis for this thought is that BGP and MPLS go hand in hand for a lot of things (MPLS VPN) and so why not just go for the comp!?

This brings us to today when I took, and passed the exam with a score of 905 (of the reqd. 835). All in all I would say that the exam was actually easier than I thought it would be, this could be because there are not cert guides for both topics and therefore you are reading books that you may read at CCIE level so there were undoubtedly some subjects which I felt VERY weak on, the biggest of these I would say was LC-ATM as I have NO prior knowledge of ATM and don’t intend to ever use it, I dare say this comes from the fact that I am coming into the networking profession as ATM is making it’s way out…

CCIP has 4 exams in total to complete and today’s exam coupled with the ROUTE exam that I completed for the CCNP means that I only have the QoS exam left. I do have some experience in QoS as I studied it for my job (and subsequent job interview) and also come in contact with it on a regular basis at work.

I am going to start off by reading the QoS Cert Guide by Wendell Odom et al and then will most likely also look over the QoS sections in the CCIE R&S cert guide so that I am fully prepared.

At the moment I am aiming for a mid-April completion date on this but as usual this may get moved forward/back.

Thanks for reading.

David

Asterisk test calls from the CLI

I know this is a little off-topic for a Cisco blog but anyway, whilst I am learning some voice stuff I may post something related from time to time.

I have recently been having some issues with my home Asterisk box where even though there are no connection drops to my home internet connection after some time the SIP trunk between my Asterisk box and my SIP provider (www.sipgate.co.uk) would drop and go into the state of UNREACHABLE and the only way I could get it to come back up would be to reboot the box.

There is no pattern as to when this was happening and the only way to tell would be to either try and make a call (it would just give the busy signal, or just die) or to check on the asterisk command line, this also meant that if people were trying to contact me whilst the trunk was down they would just me welcomed by a ‘the number you have called is not in-service’ message.

One thing that did seem to help is making sure that there are regular calls in/out of the box but this meant manually calling to/from the VoIP system and I always seem to forget.

I looked into several options and then discovered the magic that is the Asterisk spool directory, you can place a call file into the outgoing spool directory and as long as the file modification date is not in the future it will instantly run said call file.

What I have done is set up a bash script to run every 30mins to call a pre-determined test number at my sip provider and play a ‘hello world’ message.

The script for this is as follows: Continue reading

MPLS QoS Marking : The rebuttal

Earlier today Ivan Pepelnjak over at IOS Hints (url / @ioshints) posted a piece on his blog in which he mentioned the behaviour of MPLS QoS markings and how they don’t copy over upon label imposition at the edge-LSR (the post is here).

Having only looked at this very same topic a couple of weeks ago I was almost certain that this was not the case, and so I set out to lab it out and either prove myself or Ivan wrong….

My setup for this lab is as follows:

Continue reading