On Fri, May 16, 2014 at 03:23:13PM -0400, john boris wrote: > I have to rebuild my remote Backup Server (A place for my servers to backup > to hard dirves). I currently have a LINUX system with a RAID 5 array of > 300GB SAS drives (Total 1.5TB) which has to be increased to 4TB or larger > (sorta depends on the cost) We are virtualizing 22 of my servers which > currently use on board tapes for Master Backups and then do differentials > each night to my Backup Server over our WAN at night. Because this server > will now be holding Master Backups I need to grow the space. I don't have > the money nor budget to get any dedupe system or some other appliance. > > I started looking for drives and hit the smorgasbord of Green/Red 32mb/16mb > cache and the prices are all over the place. I can get a 1TB drive for $133 > (approx) but the 500GB drive is $270 with a smaller cache. Same > manufacturer and distributor. My RAID system has 8 slots which I want to > use. There will be two arrays in the system. RAID1 (Mirrored for the oS) > and the rest of the slots for RAID 5. Currently it is all one big array and > also uses LVM which I am not going to use when I rebuild this thing. > > So I am looking for some insight on what performance specs I should be > looking for in such a project. I must confess as I type this I probably > will also look at a NAS unit that would be comparable size and cost. > > My systems use a Backup program from Microlite (BackupEdge) which works > just fine for what we do and hasn't failed me yet. (looking for some real > wood to knock on).
You have a backup server, it has 8 3.5" SAS/SATA disk slots, and you want to backup 22 machines nightly? You don't want RAID5. Use RAID10. 6 x 3TB will get you 9TB of usable space, and a rebuild on a failed drive will involve much less overhead. Your NICs are likely to be the bottleneck. The per-disk cache is not going to be interesting, because backups are large contiguous writes and large contiguous reads. SAS vs SATA isn't going to help unless you're buying dual-port drives for controller redundancy, which you didn't mention. 7200RPM SATA disks with a 5 year warranty run about $200 each. (WD Black at NewEgg.) -dsr- _______________________________________________ Tech mailing list Tech@lists.lopsa.org https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
