When you’re first introduced to an environment you’ll have the ever fun task of working out which machines should get the most time; and that order seldom matches which machines actually need the most attention. To help me prioritise I’ve worked out a simple importance rating system to show where I spend my time. Below is a simplified version. I use it to assign a single importance number to each machine, and then I allocate a certain amount of time each day to work on the issues, requests and improvements I’ve got in my todo list for that level. Read on →

Although it’s a rare Unix machine that doesn’t run at least a couple of custom cronjobs it’s an even more special snowflake that does them properly. Below are some of the more common problems I’ve seen and my thoughts on them. Always use a script, never a bare command line. A parenthesis wrapped command-line in a crontab sends shivers down my spine. Nothing says “I didn’t really think this through” and “I’ve done the bare minimum to make it work” in quite the same way. Read on →

I’m a lurker on the Puppet mailing list and after some discussions John Arundel has stepped up and done the organising for the first Puppet London Users Meet - Thursday, March 22. I’m not using Puppet yet but I’m thinking of heading along to hear peoples adoption stories. I’ve also been thinking about the lack of a sysadmin community in London since GLLUG became a lot more newbie friendly and SAGE-WISE faded out. Read on →

“The Google team found that 36% of the failed drives did not exhibit a single SMART-monitored failure. They concluded that SMART data is almost useless for predicting the failure of a single drive.” – StorageMojo - Google’s Disk Failure Experience There have been two excellent papers on disk drive failures released recently, the Dugg and Dotted Google paper - Failure trends in a large disk drive population (warning: PDF) and the also excellent but less hyped Disk failures in the real world: What does an MTTF of 1,000,000 hours mean to you?. Read on →

Here’s one for the sysadmins in the crowd; if you were asked to show the following how long would it take you to gather the information? Which of your file systems have the fastest growth rate? Which are the most under-utilised? Which haven't changed by more than 5% over the last month? If you use Nagios you can cheat and work out the full drive size from the free space and percentage used reported by the disk checks, but that’s… icky. Read on →

When it comes to command line options GNU ls already uses most of the alphabet, so for my own sanity can someone implement a -j that doesn’t change the behaviour much from a ls -alh? It’s my most common typo and I’m willing to offer beer to remove the problem. I could learn to type better but this is easier ;)

Tomorrow sees the unofficial start of FOSDEM 2007. A ride on Eurostar, meet up with some of the London techs, food and then to the usual pub in the evening - it’s the only way for a Linux geek to spend a Friday night in February. This year we don’t have RMS (no song! Oh YES!) and I’ve now (twice) seen the talk I was most looking forward to (Puppet - good talk) so I think I’ll be spending more time in the dev rooms and less in the main tracks. Read on →

So, another full year of my life is over and done. As years go it’s not been the best one. Family troubles, time (and money, lots of money) spent dealing with lawyers and the passing of my grandfather, someone I saw nearly daily and often find myself thinking about, have all conspired to stop that annoying smile I often get. This post is a little more indulgent than usual but it’s my birthday and I’m full of cold caffine and napalmesque curry - so tough! Read on →

I’m not too keen on yesterdays UGU tip of the day and it doesn’t take much to make it work a chunk better, so I thought I’d whine about it on my blog. Here’s the original snippet: grep -v "#" /etc/hosts | awk '{print $1}' | while read host do ping -c 1 $host done But this has some very fixable caveats. It doesn’t deal with blank lines, it’ll try and ping IPv6 addresses (and too many distros put IPv6 entries in the host table these days - even if you disable the IPv6 options) and it will ignore any lines that have a comment, even if the comment is after the field we want. Read on →