On Mon, January 25, 2010 15:44, Daniel Carosone wrote: > > Some other points and recommendations to consider: > > - Since you have the bays, get the controller to drive them, > regardless. They will have many uses, some of which below. > A 4-port controller would allow you enough ports for both the two > empty hotswap bays, plus the dual 2.5" carrier. Note there are > 4-in-1 5.25" versions of those, too.
Yes, I found the 4-in-1. If my spare space is 5.25" I'll probably go with the 4x on general principles (prices aren't so different). Or because, as an American, I'm required to automatically consider more to be better :-). > - Don't be afraid to dike out the optical drive, either for case > space or available ports. Almost anything else is a better > tradeoff: CF to ATA, or ATA laptop disks, can fit anywhere in the > case as rpool. USB sticks are fine (even preferable) for intalls, > and it sounds like the drive is located awkwardly for use as a > burner anyway. Put the drive in an external USB case if you want, > or leave it in the case connected via a USB bridge internally. It's for installs and rescues, mostly, which I still find more convenient on DVD. > - If you decide to mirror with bigger drives (even if next time > around, rather than immediately), you can reduce the risk of the > single failure since you have extra bays: attach the first bigger > disk as a third mirror, then replace the second disk with a bigger > one, then remove the last smaller one. Keep a free slot for this. In future, when I have extra bays, definitely. In fact, without extra bays, I should probably connect a spare USB drive of suitable size as an extra mirror during the upgrade. It won't help performance, but it will help safety. > - Since you have 7x 400, you might as well use them. Stick with your > mirrors, adding a third set plus a hotspare. Or, if you can be > bothered spending the time to rearrange, raidz2 for some extra > space (defer the next upgrade longer, keep more snapshots until > then). I'm nearly certain to start with adding a third 2x400 mirror. The only issue is two more drives spinning (and no way to ever reduce that; until pool shrinking is implemented anyway). I see RAIDZ as a losing proposition for me. In an 8-bay box, the options are 2 4-disk RAIDZ2 sets, which is 50% available space like a mirror but requires me to upgrade in sets of 4 drives, and exposes me to errors during resilver in the 4 drive replacements; or else an 8-drive RAIDZ2, which does give me better available space, but now requires me to replace in sets of *8* drives and be vulnerable through *8* resilver operations. I don't like either option. > - 7x 400 will make good rolling backup media, too, in your spare > hotswap bay(s). At some point I'll probably go to some sort of external disk box for multi-drive backup. So far I'm committed to single-drive backup. (Current drives are 1TB, current pool is 800GB.) > - I've had mixed results from thumb drives, including corruption. > You can always mirror those, too; I consider it mandatory if > booting. Beware that moving them to different usb ports can > currently cause boot failures. Device selection seems to be > important, but there's little way to know beforehand. My backup scripts are a bit at risk from weird USB port issues with disk naming as well. However, the namespace doesn't seem to have any possibility of overlapping the names of the disks in hot-swap SATA enclosures, so it can't overwrite any of them by any mechanism I can find. -- David Dyer-Bennet, d...@dd-b.net; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
