Around the 8th of June 2009 GB7CD started to fail, the PC running the repeater like most D-Star gateway servers was simply of too low a spec to be utilised for any period as a server. As such a number of components failed and or were about to fail. Bottom line, it didn’t have RAID, nor did it have anywhere near sufficient cooling capacity and as such the CPU and the Motherboard got quite literary fried.
I got delivered the server for repair which had originally been donated by another Amateur. Formerly used as a rack mounted media server, no doubt to which it was very suited. But in terms of keeping something you want to maintain online for as close to 24/7 as possible then from the outset it was naturally the wrong choice.
Reading other repeater websites, it seems whilst groups have been forthcoming with funds for the ICOM hardware there has been a general over optimist approach to hardware dependability. Consider that in the first 4 years hard disks of server quality will fail at a rate of 10% a year. After 4 years this increases significantly year on year. Consider the user of lower quality, cheap consumer hard disks and you’re asking for trouble. The lack of any form of RAID on the original GB7CD installation was regrettable as without access to a working system or a backup of the user registered accounts you create yet more work for yourself when you come to reinstall the server.
Sticking in any form of cheap desktop computer with little more than desktop components even for a short time is pointless. You have to register users on it, do you really want to have to register them again if it fails a week later?
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The Right Hardware
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Quite frankly the number of people in Amateur Radio that are “experts” in computing never astonishes to amaze me. Before you decide to go build your own computer out of bits you have floating around, consider that you can obtain cheaply, maybe even free a quality rack mounted server 2 to 4 years old from many companies and corporations. On eBay even decent boxes are floating around for £150 to £400 with ample abundant parts should something go wrong. You might wonder why you obtain quality servers at prices cheaper than a comparable desktop. Its simple. Newer servers are more energy efficient. Imagine you are the Halifax bank and you have an installation of 1000 HP DL580’s; If you could replace those servers with hardware that’s maybe using 200 watts less and has more computing power, wouldn’t you drop the old ones too?Â
What you’re looking for in server hardware is at least redundant disks and redundant power supplies. Depending on the server manufacturer and model you might have 2 to 3 power supplies all hot swappable. I’d suggest you have a spare sitting there in case one goes, reducing the time your machine doesn’t have a online spare. Notice I’m talking about keeping your box online for as long as possible. Surely that’s got to be the goal, and is it really justifiable to let the server fail for the sake of a few parts that together wouldn’t cost more than £50.
Cooling as with the RF side is important, hot swappable fans are generally the norm in server larger than the smallest 1U form factor, again keep a spare one or two so should a couple fail you don’t have to take it offline to protect the hardware.
Considering the low disk usage of the D-Star gateway software RAID 5 seems a bit like over kill. Opting for Mirroring with a hot standby seems more sensible, you should have improved read access and the ability to lose two hard disks.
Other options include getting servers with redundant ram and even redundant CPU’s. That’s where I drew the line, having a good pick of servers to chose from I did consider something like a HP DL580 with redundant RAM but it’s probably a bit overkill. I opted for an IBM x360. 2GB of ram installed and 4CPUs plus mirrored disks. I see no reason it won’t be running for the next 5 years without major problem. It needed before being installed on site a new FAN and a new Hard disk which were found for less than £50 for both on eBay.
Some pictures that might interest you:
