On Thu, 8 May 2008, Ross wrote: > protected even if a disk fails. I found this post quite an > interesting > read:http://blogs.sun.com/relling/entry/raid_recommendations_space_vs_mttdl
Richard's blog entry does not tell the whole story. ZFS does not protect against memory corruption errors and CPU execution errors except for in the validated data path. It also does not protect you against kernel bugs, corrosion, meteorite strikes, or civil unrest. As a result, the MTTDL plots (which only consider media reliability and redundancy) become quite incorrect as they reach stratospheric levels. Note that Richard does include a critical disclaimer: "The MTTDL calculation is one attribute of Reliability, Availability, and Serviceability (RAS) which we can also calculate relatively easily." Notice the operative word "one". The law of diminishing returns still applies. Bob ====================================== Bob Friesenhahn [EMAIL PROTECTED], http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
