I have three (linux) servers in the office, stacked in the corner behind the desk.

One is my original server, an old P-75 that I bought from Secure Computing seven years ago. It’s been upgraded over the years; I added a new harddrive, a bit more memory, and I upgraded the CPU up to the awesome power of a P-133. These days, it’s stuffed in the corner as a firewall and my wife’s email server, and is otherwise consuming kWh and manufacturing dust-bunnies.

The second is the backup mailserver. A while back my 486-based backup box coughed up a harddrive-ball. In the search for a replacement, I found a whole machine for $10 more than the harddrive it contained, so I bought it. It’s a P-100 with 48Mb of memory and 1Gb of disk; more than enough for its single purpose. It used to be offsite, but I lost my free hosting when Baltimore became HP, so I took the backup server home, and moved the primary over to where the backup used to be.

The third is a machine I inherited from Baltimore; a Dell server, P-733 with 128Mb and a 40Gb disk. Recently I upgraded the OS to Ubuntu, which I love! Over the last couple of years this box has become the primary internal network server. I’ve added disk, memory, and CPU; moved services (email, house control, yadda yadda) from the old server.

Anyway, back to the subject. I was chatting with my brother-in-law before Christmas, and the topic of electricity came up. He has been aggressively replacing lightbulbs with CFLs, installing timers, and so on. His hydro bill was almost a third less than mine! Now, my kids are the ones who run into the house and turn on every light, and are atrocious at turning them off again; I’m sure that accounts for a significant portion of the difference. Until the recent window upgrade my house was a sieve, so I’m sure my furnace runs a lot more than his does. But nagging at the back of my brain for a long time was a comment I saw discussing computer power use. Estimating the power consumption of my servers suggests they account for somewhere between 10% and 15% of my total power consumption!

Obviously, It was time to do something. Solar panels were briefly considered; I have a beautiful expanse of southeast facing roof, but cost and ROI still aren’t there for southern Ontario. And besides, it should be relatively easy to reduce the power consumption of my computer network without inconveniencing anybody; if I start small, the task is likely to get finished. As an added bonus, reducing the server load means that the UPS will last longer during a power outage, and the room will be cooler in the summer.

Also just before Christmas, I read that Linksys had introduced a new model (version 5) of the WRT54G wireless gateway that did not run Linux. So when I saw a stack of version 4s on sale at Best Buy, I snagged one. I’ve moved e-mail to the more powerful server, and installed OpenWRT on the Linksys; ta-dah! One server eliminated.

Also before Christmas (coincidence? I think not!) we filled up the server disk (the new camera takes large pictures :-). I’m not quite ready to drop a wad of cash on a proper RAID array, but I did pick up another disk for the server.

Which brings me to the second half of the subject line. I’ve been a big fan of Vmware and related technologies for a long time. After listening to a seminar on Xen and virtualisation at work, it hit me; I could move the backup mailserver onto the P-733 box! So, that’s my next IT hobby project.

One more bonus? When I’m done, I’ll have enough spare hardware to start building a replacement for persephone (the main webserver)… (ducking)

(Update in 2025: two servers, six mini-pcs, a Turing Pi, and all the network gear - I’m spending about $20/month on electricity just for the computers.)