On 19.12.2012 12:25, Miao Xie wrote: > Hi, everyone. > > As we know, there is no backup function for qgroup. when the problem > occurs, the users must recover qgroup configuration manually, it is not > convenient. And besides that, some users might want to import an existed > qgroup configuration into a new filesystem. Btrfs does not have such a > function,it can only be done manually. > > So we want to implement btrfs qgroup import/export commands. > 1)'btrfs qgroup export' commands will export qgroup tree > into a user's specified file.(stdout by default) > > 2)user may modify the configuration file firstly and then > import it into the filesystem.(by 'btrfs qgroup import' command) > > The file may be formated as the following: > > Qgroupid is_compressed is_exclusive limited_size parent > ---------------------------------------------------------------------- > 0/1 0 0 10G 1/0 > 1/0 1 1 20G --- > > If 'is_exclusive' is set, 'limited_size' corresponds to max exlusive size, > else max referenced size. Here 'parent' exclude ancestral qgroups. > > Is there any comment about this idea? The configuration only really makes sense in combination with the existing subvolumes. Even if the target has subvolumes under the same name, they might have different internal IDs. So it might make more sense to address the level 0 qgroups by name. Also it might be misleading to apply a configuration to an existing fs, as it currently is not possible get a correct accounting if the fs is not empty. Rescan is not yet implemented. So instead of just saving and restoring the qgroup config, it might make more sense to create a new filesystem including all subvolumes and quota config from a config file. But, I'm not completely convinced that this is a features that is needed frequently. If I want a standard deployment, I simple write a script that creates the fs + subvol + quota. -Arne > > Thanks > Miao > > > > > > > > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
