At school, a guy up the IT ladder said we could use some of the computers that have been sitting in the closet for whatever we want. There are currently 11 in there!
The computer club wants to setup a server cluster running SuSe, with one being dedicated mysql, and all hard-drives in one RAID array. None of us know much about RAID, though. (Note, though, that each hard-drive is a mere 6 gigs! It’ll be fine all added up, though.)
We want to run an Apache master that’ll have individual Apache slaves serve up the pages or something, but none of us know about clustering, either. We’ll learn, fast.
Any advice on this? We have lots of computers, and we want to do something neat with them. We also have lots of monitors.
Oh, the same guy that said we could use them said that he would let us use the more powerful brand-new computers to have a Counter-Strike LAN party and he’d take off DeepFreeze (this awful program that resets the HD every time you restart; we took out the battery from the desktops to reset the BIOS and then formatted the HDs to get rid of it on the old computers) for us.
any particular reason for a raid? if one of the harddrives in a raid array fails all of the other hard drives are unusable. if these computers are sporting a 6 gb capacity and have been in a closet, then you are probably looking at hard drives that are 6+ years old - the average life of a hard drive being 5 years under normal usage, these being school lab computers they could expect an even shorter life expectancy.
clustering is different from a raid array also - your best bet and the one with the highest chance of success is to create a small lan network with 1 computer being the mysql database and group file storage, 1 computer being the “master” computer if you even want to call it that, and the other 9 being normal client computers.
if you can get that setup and all the computers seeing each other, the mysql database setup properly and perhaps some form of linux domain authentication using the master computer, i would then evaluate cluster computing as an evolutionary step in project scope.
another project addition could be to setup a mail server based on IP on the master computer and have it to where you can check your emails on the various computers and send each other email across your lan.
to take it even further, create a web page that serves as a “start” page for the network where you can login using the mysql database and have access to certain web-based apps - perhaps use an email interface such as horde to access your mail server and check your mail.
also you could setup a simple ajax graphitti wall that would let the users of the 10 computers talk to each other in real time.
You need a special hard drive controller if you want to do it in hardware… but you can do it in software with any 2+ off-the-shelf identical hard drives (hell, with LVM they don’t even have to be identical, although techncially it’s not RAID)
/me knows because /me has a 600GB RAID0 array upstairs
I also tought, as my newly bought server had an RAID with two harddrives. That when one crashes the other one survives and has the exact same content so the computer doesnt loose all stuff on one of the drives.
It depends on the raid level your running. Raid will provide full redundancy at level 5 but you need 3 or more disks for this to work, some admins use level 0 for performance, there is no redundancy at this level, a level 1 provides a mirror of the main disk etc, have a read of http://www.webopedia.com/TERM/R/RAID.html for a far better explanation.
nice, playing with raid is fun (if your that way inclined) Raid on linux is even more fun… a hardware raid controller is the way to go for a professional setup, but playing with software raid on linux is great because you’ll learn a lot in the process, such as the different levels, you may even have to recompile the kernal for support… in the day when I was an admin, I set quite a few software raids up on Suse and it worked great.
if they are mirrored then its redundancy, but to combine them thats where the issue comes in - raid doesn’t necessarily equal stability though - i think one of those links i pointed to talks about that.
but good luck - good to see you guys are trying something and that your school is letting you - post up how it goes over the next few weeks.
Will do. RAID5 says one HD failure and everything is fine, but you’re out of luck after that.
With a backup to an 80gb external HD, we should be fine.
One question: How do you handle the HDs all being in different computers? One person was sure they had to all be together in a different place, but I’m pretty sure that isn’t true. Is there any way to network them without the slowness of a LAN?
So I’ll shutup now :thumb:
