I was curious how much data I’ve had on my computer network over the span of its existence, so I decided to plug a few data points into open office in order to visualize it. This is what I came up with. I started when I got my first personal computer, a monster of a laptop that had dual hard drives, totaling 100GB of storage. I also had a 120GB external hard drive connected to my first Linux server, and then later attached a 160GB internal drive to it as well. Two 500 GB hard drives later I had a server crash, which caused me to lose just over 1TB of data. I jokingly refer to it as “The Great Server Crash of 2007″. Ever since then I always buy hard drives in pairs. One for actual data storage and the other for backup. If it hadn’t been for that crash, the trend line would actually be really accurate.
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Computers
Data, hard drive, server
I ran a test today to make sure that all of my servers could be run off of my truck’s electrical system without any downtime. I simply ran a long extension cord from an outlet in the truck to my server closet. I then unplugged the server closet UPS from the wall outlet and plugged it into the extension cord. The UPS in the closet beeped a few times, but kept on running. I then unplugged the shore power umbilical from the truck, the closet UPS beeped a few times, and then was running off of the truck’s UPS. Everything went off without a hitch. The trucks 6.6KWhr of usable battery life should give me about 16 hours of run-time, plus whatever the closet UPSs provide on their own. The closet draws around 415W of power. This includes all of my servers, switches, and routers, except for my surveillance system.
The only downside to this setup is that I have to manually unplug the closet UPS from the wall and then plug it into the truck. In order to get around this I may just run it from the truck system all the time (with the truck’s umbilical connected to shore power) and then switch the closet over to the local outlet whenever I drive the truck.
Computers, Deuce and a Half
I know it’s been a while since my last update, but we’ve been doing a lot with the Deuce. When we first started working on the truck I thought that all of the electrical wiring in the box was going to have to be redone. John did some testing with the existing cables and figured out that everything should actually work ok. The stock umbilical cable did not seem to join with the breaker box properly, so we decided not to use it. Instead, we disconnected the generator start/stop control buttons and ran a standard household electrical cable from the inverter to where the buttons used to be and then into the breaker box. We are using an APC 900W UPS connected to six Everstart marine batteries from Walmart. Each battery is 115Ahr at 12 Volts, which gives a total of around 8.2KWhrs if I drain the batteries down to the shutoff voltage. Granted, I have no intentions of taking the batteries down to the 10.5V cutoff, so an 80% depth of discharge leaves me with around 6.6KWhrs, which is still a good chunk of change. Running the inverter at the full 900W would give me about 7 Hours of run time.
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Deuce and a Half