I have know people who have had both drives fail. That aside RAID1 is slow, you will have better performance by using RAID5, RAID6, RAID10, RAID 0+1, or any of the many other RAID levels. Remember this was a database server, a central location for the site's entire database. For one database is usually always the bottleneck so squeezing speed where you can is always a good thing not to mention the requirement for better fault tolerance than mirroring. It also wasteful when it comes to data, you are using N*2 vs N+1 (r5) or N+2 (r6). RAID10 and 0+1 are also wasteful, but may be better options than RAID5/6 depending on the application.
If I was in a situation where I was hosting a number of sites on a number of servers I would not feel as strong about avoiding RAID1 (depending on traffic), because it would not be a single point of failure for the whole operation as this database server was. The more redundancy you have or the more paritioned your setup is the less important it is to worry about the data on a single machine. There are a number of situations where running a number of machine entirely in RAM is perfectly fine and would be encouraged, but in those cases the database and file server still need very high fault tolerance. I would never use RAID1 alone for a database server unless it was a last resort and by last resort I mean, the machine is a 1U that will only hold 2 drives or the machine only has 2 SATA/SCSI ports and no way to add even a non-raid controller card... or I was 100% completely broke. Just my 2 cents... maybe 3 depending on the value of the dollar On Sat, Jan 3, 2009 at 9:22 PM, Jeff Lasman <[email protected]> wrote: > On Saturday 03 January 2009 12:17 pm, Peter Manis wrote: > > > they really should have been using > > something a bit better than RAID1 to start with. > > We've been using Linux software RAID 1 for many years and we've only > once had a system we couldn't restore from RAID (we restored from a > less than day-old backup on that one) because we didn't properly > understand the "bug" (I call it a bug) where grub by default doesn't > setup reboot from second drive in case first drive has failed. But now > we set it up correctly, use hot swap, and everything works. > > So "what's wrong with RAID1?" > > Jeff > -- > Jeff Lasman, Nobaloney Internet Services > P.O. Box 52200, Riverside, CA 92517 > Our jplists address used on lists is for list email only > voice: +1 951 643-5345, or see: > "http://www.nobaloney.net/contactus.html"; > _______________________________________________ > LinuxUsers mailing list > [email protected] > http://socallinux.org/cgi-bin/mailman/listinfo/linuxusers > -- Peter Manis (678) 269-7979
