Setting up and maintaining Linux software RAID on an Apple Xserve G5 with Yellow Dog Linux

Despite certain frustrations with our Apple Xserve G5s, I’ve found that they make decent Linux servers, especially considering their age. Recently I wanted to repurpose one as a development server, and in that role I really wanted disk redundancy for added protection of the data. Unfortunately there’s no RAID controller in these servers, so software RAID is the only option. Originally RAID wasn’t crucial and I gave up on software RAID as it seemed too complicated to justify the time spent figuring out how to do it. This time, however, it was more important and I was determined to get software RAID functioning. read more

System administrators in films

I recently watched Cargo (2009), which turned out to be a pretty decent sci-fi film (sort of a cross between Silent Running, The Matrix and Alien). One thing I particularly enjoyed about the film, however, was that a key member of the spaceship’s crew was a system administrator (and a female sysadmin at that!). I liked the way this character was important to the plot, and I was amused by the way the filmmakers gently poked fun at the geeky nature of sysadmins. read more

My Mac mini-based media centre

For quite some time I’d been looking forward to building a decent media centre, and after rearranging my flat recently I had a great lounge area, so I went ahead and built it. I’ve read quite a few blog entries about other people’s Mac mini-based media centres over the last few months, and now that I’ve been using my new setup for a few weeks it’s time to write mine! read more

New graphics card (ATI Radeon HD 4870) on my Mac Pro

When I started playing Bioshock on my ageing Mac Pro, I found that the graphics card (a Nvidia GeForce 7300GT, apparently) was so poor by today’s standards that the game was practically unplayable. I therefore decided to get a new ATI Radeon HD 4870 graphics card. Despite the fact that Apple say this card is for recent Mac Pros (Early 2009 or Early 2008), it works fine in my original Mac Pro (2006). read more

Bash script for configuring specific things on users’ Macs

Although I’ve got our Mac mini server nicely set up now, there are occasionally things I want to do on users’ Macs which can’t be done or don’t work properly via Server Admin and Workgroup Manager. However, one of the wonderful things about having an office environment consisting entirely of Macs (rather than Windows PCs) is that you can just SSH into them and write Bash scripts which can be triggered by cron (or, better still, by launchd. read more

Moving from cron to launchd on Mac OS X Server

As the usage of cron is now deprecated on OS X and OS X Server in favour of launchd, I thought it was about time I learnt how to use launchd so I could move all my cronjobs across to it. launchd is one of Apple’s various contributions to the Unix world, and its purpose is to be a single tool to take the place of init and to replace a variety of startup mechanisms such as the rc/rc.d startup architecture, cron, and inetd/xinetd. In keeping with most other technologies emanating from Apple it is simple, elegant, efficient and powerful. If you do a significant amount of Mac administration then now is the time to learn launchd if you haven’t already. read more

Monitoring disk/RAID hardware in CentOS on HP DL360 servers

For some time I’ve been having problems monitoring disk and RAID hardware in CentOS Linux on our HP ProLiant DL360 G5 servers. To begin with, I discovered that hpasm, the main monitoring agent provided by HP, does not actually give any information about the disks or the RAID controller, even though it does seem to monitor all other hardware in the server. read more