On Sun, Jan 18, 2015 at 10:43 AM, Ian Collins <[email protected]> wrote:
> Greg Zartman via smartos-discuss wrote: > >> I believe mirroring is the best practice so that if one SSD dies, you >> don't lose any data before the slog has time to write to the zpool. >> > > You won't loose any data if a log device dies or is pulled. Logs are only > read from to recover data, such as after a power failure which is why you > should devices with power fail protection. > I wanted to follow up on this comment, as I just proved to myself that you do lose your zones zpool if the log device fails. I've been testing with Intel 3700 SSDs and a couple SmartOS boxes I have. On one of the boxes, I lost the log device and the zones zpool disappears on a reboot. I reproduced it 2 times by just pulling the log device. Technically; you don't "lose" data, but you do lose your zones zpool and the box is essentially nuked. The admin has to boot SmartOS into maintenance mode, force a re-import of the zones zpool, the remove the lost/bad log device to get SmartOS too boot back up. This isn't exactly a routine maintenance task. As such, I don't think it is safe to run a SmartOS box in production with a single log device unless you don't mind have to perform minor surgery on the box to get it back up again. Greg ------------------------------------------- smartos-discuss Archives: https://www.listbox.com/member/archive/184463/=now RSS Feed: https://www.listbox.com/member/archive/rss/184463/25769125-55cfbc00 Modify Your Subscription: https://www.listbox.com/member/?member_id=25769125&id_secret=25769125-7688e9fb Powered by Listbox: http://www.listbox.com
