Dermot Paikkos said: > Hi admins, > > I'm about to buy a custom build server and wanted to know to > configure the RAID. This will be the first time I have configured a > RAID from scratch and I am a little un-sure about how the layout of > the system. > > The server will primarily be used as a file server, uses a 3Ware SATA > 8 port card and will serve about 50 users. There will initially be 4- > 5 disks installed. I would like one as a hot-spare but it isn't > written in stone at this time. SATA is for game computers and highend workstations. Use SCSI for servers and hardware RAID not software RAID. IBM has 20KRPM SCSI drives now and with the Ultra160 wide channels, data flow just screams. 4 drives with a RAID 5 over three drives with one hot-spare is a very efficient configuration. > My own thoughts were to keep the root file system outside of the > RAID. That is not necessary. Your hardware RAID arrays will look like individual drives to your software, treat them as such when you partition them. For myself, I like to make one array for the OS (/boot, /, and /usr). Then one for /home (and/or /opt) or wherever you will be storing majority of user files or shares. Last, a small array for /etc, /tmp and /var which I like to have available for reconfiguring a new OS install, but it's not needed. > What about swap? How should you configure the swap space on such a > system. Can swap space be assigned to a RAIDed file system? Should > it? Why not. If your hard drive with SWAP on it goes down, wouldn't you like it to be as safe as the rest of the server? > Is there anything else I should be thinking about or any documents > should read (I tried tldp.org but nothing struck me). Any thoughts? What I learned the hard way, with HW-RAID: make sure it is the only device on the channel. I once had a tape drive on the same cable and when I went to change it, all the drives went off line. That is not a good thing. Anytime you read, "Warning! This action may cause data loss" read it as, "make sure you have two good backups before doing this, because you _ARE_ going to need one". Test it!: load up an OS, copy some large pictures to it, large documents, and some third party software or something you can test. Pull out a drive, test the pics, docs, and software to make sure they will work while the drive is off-line, while the drive is being rebuilt and once the system if finished rebuilding. Test as much as you can with your new RAID before you trust it to a live, production server. If you insist on playing about with a SW-RAID, break it and make sure you can reboot LOL. Never remove more then one drive at a time, ever, even with the thing shut off. When you replace the drive it will need to be rebuilt before another drive can be removed, swapped or whatever. Once you got it running, stable and solid, don't mess with it. If you take one drive off-line, for any reason, that drive will need to be rebuilt before you can take another off-line. -- Scott - : send the line "unsubscribe linux-admin" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
