Hi Peter, On Thu, 10 Aug 2006, Hieromonk Peter wrote:
> In a nutshell, this system Dell PowerEdge 2900 with two Xeon dual core > processors, 8 GB Ram, with two 146 GB SCSI 10k rpm hard drives in a hardware > Raid 1 configuration, for $3,482.00. Will 146GB be enough space to store everything? You should be fine as long as you're not dealing with any multimedia files, but I thought I'd throw that question out there. > 1. Someone told me I should not set it up with Raid 1 -- that I should set > it up with three 73 GB hd's. He said it would be faster than the Raid 1. I > don't know much about Raid, but I gathered that Raid 5 should be slower than > Raid 1 -- if not in the writing, than at least in the reading. Which should > I go with -- 1 or 5? Any opinions? Here is a link to a page with a nice table comparing RAID levels: http://www.storagereview.com/guide2000/ref/hdd/perf/raid/levels/comp.html In a nutshell, RAID 5 is faster than 1 for reading, slower for writing. One main benefit to 5 is that a higher percentage of the total disk space is usable (more bang for the buck). In other words, with two 100GB disks in a RAID 1 array, you get 100GB usable, or half of the total 200GB. With three 100GB disks in a RAID 5 array then you get 200GB usable, or 2/3 of the total 300GB. Another downside of RAID 5 is that as you add disks it becomes more likely that one of them is going to fail sooner rather than later. > He also said that in a Raid 5, if one drive went out, the other two would > just pick up and run without the other drive until I could replace the > faulty drive, without me having to do anything. Is that right? Yes, though the same is true of a RAID 1 array. In either case if you lose a second drive before you replace the first failed drive then you lose everything. So don't dilly-dally. :) > 2. Do the drives in either Raid 1 or 5 have to be *exactly* identical? > That is, if a drive fails a few years from now, and I can't get an exactly > identical drive to replace it, will I be ok as long as I can get one that is > the same size, although perhaps a different brand or model? Or would I have > to replace all of the drives? No, they don't need to be exactly identical (unless you end up using some bizarro proprietary RAID system). The replacement drive would just need to be at least as big as the one it's replacing (it doesn't have to be the exact same size) and use the same interface connection. > 3. If I go with a Raid 1, is one hd Raid controller enough, or should I get > two? I know one will do the job, but would two be better? (Like I say, I > don't know much about Raid. This will be my first experience with it.) I would recommend using a hardware RAID controller for which there is nice management software. In that case you only use one controller for the array. There are 2-port cards which can only do RAID 0 or 1. If you want to do RAID 5 then you'll need a card which has enough ports, etc. We use 3ware ATA/SATA RAID cards and have been very pleased. The open source driver has been in the stock Linux kernel for a long time and 3ware has some nice little software which gives you a web interface to the array and will email you when there's a problem. 3ware doesn't make SCSI controllers though, so if you want to go that route (which is a fine way to go) then they won't work. > 6. I've priced systems with HP and Gateway, too, and they seem to cost > more than Dell for less powerful systems. Where do you all get your > servers? Do you build them yourselves? If so, is there a better place > to get the components than Tiger Direct, PC Connection, JDR, and CDW? We're a small non-profit so we build our own (and only when there's money available). We get almost all our components from NewEgg and Buy.com. Jason ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _____________________________________________________________________ Ltsp-discuss mailing list. To un-subscribe, or change prefs, goto: https://lists.sourceforge.net/lists/listinfo/ltsp-discuss For additional LTSP help, try #ltsp channel on irc.freenode.net
