On Thu, 21 Jan 2010 12:44:29 -0800 Larry McVoy wrote: > Disks are much higher volume and are forced to be reliable "enough". That "enough" is the critical point. Check the average read failure rate of SATA drives. It is 1 per 10^14 bits for my ST3500320AS. The drive has a capacity of 512 bytes/sect x 976773168 sectors. I.e. I will get at least one read error when I try to read the entire disk 25 times. If I build a RAID out of 5 of this drives I only need 5 reads through the RAID to get a read error and the RAID will degrate. > If you aren't backing up with a crc then you are doing it wrong. With a CRC you can detect bit rott. (Probably. Somthing like MD5 or SHA-1 is mch better then a CRC.) But you can't repair the defect data. So you want ECC... -- tschüß, Jochen Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/ _______________________________________________ TUHS mailing list TUHS at minnie.tuhs.org https://minnie.tuhs.org/mailman/listinfo/tuhs