Thursday, 2 February 2012

Well, someone has to test it

I was thinking that the blog is not a bad way to explain a bit about how the network upgrade is going at A&A. We have the status pages, which are fine (well, maybe not, they need some work), but I can probably say a bit more here...

So, where are we?

The good news is that this is all just happening. The crew working on this are actually doing a good job planning and designing and, well, making it happen. They have some key deadlines they are working to, but so far everything is going pretty well. I almost feel like a director for a change, rather than an engineer. Not sure if that is scary or good.

The fun with the network this week was rather unfortunate, but yesterday we did set up the pair of route reflectors and connected almost everything up (couple of DNS servers to go). What we did do is connect the existing routers and LNS to them as well. This means we have one core network (over the old and new racks) and can start moving things.

One of the main things was testing the new link to our favourite telco. This is the primary reason for all of this - so that we can operate more than a gigabit of traffic. Initially we will be running with four gigabit fibres in to them and up to two gigabit of traffic. The load can use any of the four links in any combination which nicely allows us to run three live LNSs at well below capacity and have a fourth as a backup in case any fail. Right now we have less than a gigabit of traffic and everything can run through one LNS. The trick is to make sure that any one failure, and ideally even two failures, do no push any link or any router over capacity. The new rack can expand with more LNSs and routers to around 4 gigabit of traffic before we have to rethink things and that is probably quite a few years of expansion.

So, new host link works, and Paul has been testing his home line last night. He found and fixed a few MTU issues, but yes, it works! Well done.

But right now he as a whole rack, ten FB6000 series gigabit routers, two gigabit fibre links to the telco, and his one FTTC home line using it.

Of course, whilst this does seem like overkill, it makes no actual difference. Things go as fast as his line, as normal... We do, after all, aim not to be the bottleneck. Just amusing to think of all of that infrastructure and capacity for one line.

But it means we can do a simple LNS switch to move customers over, and get the old host link moved to the new rack so we have all four gigabit feeds. It looks like we have managed to get links via different floors (above and below us) in to the telco as well, which is good for redundancy. We also have them via different technologies (WES and EAD) so different termination kit in the rack. All of the kit in the rack is dual power and there are separate incoming power feeds.

The other good news is that this new rack also has a link for Ethernet customers. That means we can offer Ethernet via London and Maidenhead for even more redundancy. That is a link to be tested soon as well.

I'll post more on here as we make progress - but this week is key. From now on it is basically plugging things in and moving things over, and testing testing testing.

As for host names, there are a few changes. We are keeping the telco links (LNSs) as gormless (can't think of a better name), though there is a/b/c/d of them now. We are changing the edge routers from armless to aimless, an old name we used to use for edge routers, and there are a/b/c/d of them too. We have Ethernet edge routers which are core route reflectors called weightless. We still have doubtless and careless used for testing, direct L2TP and data SIMs.

The good news is that FB6000's use under 30W when running flat out, so no issues with power usage and keeping things cool. It is a very "green" network that we run.

Watch this space...


  1. Which of the Telehouse buildings is your new kit in, then - are you in the shiny new West building?

    (or would you prefer not to disclose)

  2. No, but it is one of the refurbished rooms with more power...