To add: Even if you have great faith in ZFS, a backup helps in dealing with the unknown. Consider: - multiple disk failures that you are somehow unable to respond to. - hardware failures (power supplies, motherboard, RAM). - damage to the building. - having to recreate everything elsewhere - even another system - for a special reason.
ECC RAM will help ensure that the data given to ZFS is error free. ZFS will ensure that it's able to detect errors while writing to the storage medium. There are still issues such as disks reporting that data has been written, but not having written it yet. Could someone elaborate a bit more on this aspect, please? -- Sriram On 11/16/10, Edward Ned Harvey <sh...@nedharvey.com> wrote: >> From: zfs-discuss-boun...@opensolaris.org [mailto:zfs-discuss- >> boun...@opensolaris.org] On Behalf Of Toby Thain >> >> The corruption will at least be detected by a scrub, even in cases where > it >> cannot be repaired. > > Not necessarily. Let's suppose you have some bad memory, and no ECC. Your > application does 1 + 1 = 3. Then your application writes the answer to a > file. Without ECC, the corruption happened in memory and went undetected. > Then the corruption was written to file, with a correct checksum. So in > fact it's not filesystem corruption, and ZFS will correctly mark the > filesystem as clean and free of checksum errors. > > In conclusion: > > Use ECC if you care about your data. > Do backups if you care about your data. > > Don't be a cheapskate, or else, don't complain when you get bitten by lack > of adequate data protection. > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss > -- Sent from my mobile device ================== Belenix: www.belenix.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
