A.J. Clark

One thing I wished that Linux could do was to dynamically grow a partition online. This is something I was accustom to in HP-UX, AIX and even Solaris. It’s a pretty common operation to do in an enterprise environment with SAN LUNs. Lets say I have a web server running Apache on Linux. The htdocs dir sits on a dedicated SAN LUN and is slowly filling up. This server is a production box. Everything is using LVM. Before we can expand the FS, LV, or even the VG we need to grow the physical parition that the VG lives on. We expand the physical LUN size on the SAN, and fdisk the partition in Linux but linux still does not see the updated partition table size (without a reboot) – this is not good!

However, do not fear! I come across the very command to address this problem: blockdev –rereadpt /dev/sdX

Sigh… I wish I came across this command years ago!

I’ve just come across this awesome little utility called “DMT” for Speedtouch and similar routers. Speedtouch routers have a telnet interface that let you access a fairly powerful command line interface. You can configure advanced aspects such as IDS, SNMP, etc. DMT is essentially a GUI to the telnet interface providing a complete (and awesome) overview to your Speedtouch router. Checkout the screenshot below.

DMT can be downloaded from http://www.kitz.co.uk/routers/DMTv7.htm

I’ve just moved in to my new home and I decided that I will get rid of my old long cat5e network cables and order specific length Patchsee Cat6a network cables. Whilst I don’t actually need these cables, they’re aesthetically pleasing and technically superior. I highly recommend them!

Patchsee Cat6A UTP cable

A screenshot from a console session to a Rackable server:

I recently I joined a leading e-commerce company as a UNIX system administrator.

This is where I work, and this is what I do:

I spent Friday wiring up RJ-45 patch panels to go in to our new lovely APC racks. Usually, we pay a contractor an extortionate amount of money to do this, but there is a recession,  you know! It’s a fairly simple thing to do, cut once, measure twice, learn the wiring standard, bla bla – but boy does my hand hurt after doing this all day!

Deleted your /etc/passwd{,shadow,group} file(s) ? No problem! Debian keeps a backup copy of your gshadow, shadow, group and passwd files in /var/backups!

Hurray!

Today I decided to go out and purchase a digitial photo frame as a parting gift for my friend. I would usually only make such a purchase on the World Wide Web (e.g. Amazon) because of the bigger range and lower prices but I needed this gift for today as my friends are leaving for London tomorrow.

I offered to lend my friends a hand with carrying their luggage to their new apartment in London tomorrow, and as it turns out they booked me a ticket to stay with them all weekend – returning on Sunday. So it looks like I am spending the weekend in London.

For reference, the digital photo frame is a Sony DPF-V700B . It even has a remote and a HDMI connecton, woohoo!

One year finishes as another year readies. Looking back, 2008 has certainly been one of the most important years of my life. I have loved and lost a person who was very important to me, but I have also learned a lot about my character, and who I am.

For me 2008 started with a call (on Skype never the less) from my then girlfriend explaining that she is leaving me for another person. This hit me harder than Thor’s hammer. I then had to go to London for work reasons and spend a week in a hotel alone. Dark times indeed.

As the saying goes: “Time is a (the?) great healer” indeed things did get better as time goes on. I had been with a partner for such a long time that I had forgotten what it feels like to be single and free. It was such a released burden to make decisions which are entirely for your own interests, not having to consider your partner.

I realised that Thor’s hammer is indeed all powerful and I was still somewhat filled with darkness and rage. I decided that I needed a way to channel and release my anger and decided to take up running and fitness.
Up until this point I was somewhat unfit, working in IT and never really doing any cardio in this millenium. This was going to be a challenge.

The idea that my running was fueled by rage give me confidence in what I was doing. Being a sysadmin, and therefore logical, I decided it would be a good idea to first come up with a training plan and a way to monitor my goals and progress. I developed a fitness training schedule and purchased a Nike+ sport wristband to monitor my running. God this felt good. re-taking charge of my own life felt extremely self-satisfying.

I started out with simple running goals of one mile per session, then two miles, then 5k, then 10k, then 20k, and so on. I decided to focus on consistent mile times rather than all out distance. It was one thing to run a mile in 5:59 flat, but how about running 10 miles at 5:59? a challenge!

I decided that I wanted to incorporate weight training in to my exercise plan. This meant that I had to structure my diet to take onboard as much protein as possible. Unwanting to eat a ton of meat every day I decided to purchase Whey Protein powder from Maximuscle. I also decided to lower my intake of carbs (which argubaly curved my ability to run) and instead focus on burning excess body fat.

Within several weeks I felt several times stronger (with visible biceps, rawr) and a lot less body fat – in preperation for that six pack abs.

My work was going well too. The company that I work for build and refurbish power turbines. They have done for a very long time. They have standard well-defined design tools and processes. Unfortunately these tools insist on a legacy Unix environment. The engineering departments currently use Solaris 2.6 for production work. As the Unix system administrator it is my job to support this environment. or atleast the server side.

At first glance this is a very bad thing from an IT perspective. A reliance on proprietary legacy applications means keeping a legacy operating system which means keeping legacy hardware to run said operating system – eventually all of this will fall down and the company will suffer.

After 1.5 years of arguing with the IT managers, the business, and engineers, trying to make everyone understand the risks and implications of a legacy environment like ours nobody is budging. I have decided to accept that the people which whom I am lobbying against have no interest in shaping the future, or moving forward. I secretly think their strategy is to retire and it won’t be their problem any more.

With all that in mind I did some reasoning and thinking and I decided to do what I can to help preserve this legacy environment for many years to come. First of all, the environment is stable and frozen. The only data to change is the user application data (e.g. CAD files).

Secondly all hardware, although legacy, is under maintanence so it can be kept running almost indefinitely. Even if the server caught fire, it isn’t impossible to buy legacy Sun servers to reload Solaris 2.6 on.

Thirdly, the entire Unix environment (NIS) is rather cleverly served from the NAS (EMC Celerra). This means that to rebuild the Solaris 2.6 production servers all that is required is an OS reload and the server to be bound to the engineering NIS domain – all data is served automagically via NIS automounts.

Fouthly, I decided to rip out any legacy complicated infrastructure that may hinder rebuilding this legacy environment. Risk notifications were sent out, and disaster recovery plans created.

At this point people will probably be thinking why Solaris Containers or technologies like Transitive weren’t employed. The truth is, they were, and they were deemed unsuitable for the job. The Solaris 2.6 applications did not work entirely in Solaris 8 BrandZ or Solaris 10.

Transitive is basically Solaris 10 anyways, and although fine for running single applications, it proved to be too much of a niche in my absence – why should I be a single point of failure for my company? Although it would keep me in a job I guess.

Fast forward to the end of 2008 and things are great. I have met a special person, and planning an exciting 2009 in a new location.

Merry Christmas && Happy New Year!