Adventures with Lustre

26th March 2009 by Mark Sutton

For the last few months we’ve been busy integrating, testing and tuning Lustre for use on our hosting platform. I thought I’d share some notes… Lustre is most widely used in HPC settings and there seem to be relatively few …

Preparing Procurve Switches for Production

23rd March 2009

We recently took delivery of some new Procurve 5406zl switches for our Cloud platform. As with any new device being attached to the network there are quite a few tasks that must be done before the it can be plugged into the production network.

.htaccess revisited

19th March 2009

About a year ago Dawid posted about the performance of .htaccess files. We decided to revisit these tests to compare the performance of .htaccess files on local disk and network filesystems.

Getting to know Lustre

17th March 2009

Lustre is a complex cluster filesystem aimed at super computing clusters, offering scalability to many Gigabytes per second and Petabytes of raw storage. We’ve been testing it for some time as a base filesystem for virtualisation and I wanted to …

Process list for OpenVZ containers (vztop)

17th March 2009

The standard linux task list shows you each process and the resources (e.g. CPU, Memory) that they are consuming. However, if you run top on an OpenVZ host server, it doesn’t show you the container ID of each process. Fortunately, …

Choosing the right switch for storage

16th March 2009 by Mark Sutton

Storage over Ethernet is a hot topic in the web hosting datacentre at the moment. With several excellent storage protocols to choose from and plenty of vendors offering product there is certainly a lot of choice in the marketplace. But it’s easy to overlook the importance of the Ethernet switches that are going to be carrying your data – after all you just spent a fortune on ‘redundant’ storage right?

Memtest Over Network

16th March 2009

One rainy day we had a bad feeling that one of our rackable servers had corrupted memory. The server had some intermittent stability issues and hanged from time to time. It prompted us to test memory on all rackable servers …

Resolving bind zone transfer issues

11th March 2009

Today, a fax machine at the office started complaining that it couldn’t send emails. No useful error messages or anything… After some digging it turns out the fax machine was getting SERVFAIL from the name server. This nameserver carries slaved …