I just saw a new feature that would be in a flag. Large block support. That would be available in newer versions but won't be in older, but will still be on version 5000. So if you had a pool with large blocks enabled you would need to upgrade to or use a distro that had large block support to import. linda On 4/21/15 9:33 AM, Andrew Berg wrote: > On 2015.04.21 09:08, Munir Nassar wrote: >> On Tue, Apr 21, 2015 at 7:33 AM, Andrew Berg >> <aberg010 at my.hennepintech.edu> wrote: >> >>> See the zpool-features man page. It varies by feature. Some will completely >>> prevent import in this case, while others may simply only make the pool >>> read-only. Also, some features are not mandatory at upgrade time and will not >>> be enabled automatically. If a feature is disabled, support for it is not >>> required for import. >> This is a bit misleading, as the feature would need to have been >> disabled from the start. > Actually, I was mistaken about features not being enabled automatically. > Features are enabled automatically, but are not necessarily active. Any > enabled, but not active, features do not prevent import. > >> Lets say i create a feature of supercompressor which compresses >> everything with my super secret proprietary algorithm(so secret that >> even decrypting is a closely held secret), disabling this feature only >> affect NEW blocks and old blocks will remain compressed with this >> proprietary compressor rendering the pool unimportable by a ZFS >> implementation that does not understand the supercompressor feature >> flag. > A compression feature would always be active, so yes. However, one would be > unwise to activate this feature if one planned to ever use it on a system > without support for that proprietary feature. As I said, pay attention to which > features are going to be activated, and what support other systems have for them. > _______________________________________________ > TCLUG Mailing List - Minneapolis/St. Paul, Minnesota > tclug-list at mn-linux.org > http://mailman.mn-linux.org/mailman/listinfo/tclug-list