btrfs-replace - replace devices managed by btrfs with other device.


   btrfs replace <subcommand> <args>


   btrfs replace is used to replace btrfs managed devices with other


   cancel <mount_point>
       Cancel a running device replace operation.

   start [-Bfr] <srcdev>|<devid> <targetdev> <path>
       Replace device of a btrfs filesystem.

       On a live filesystem, duplicate the data to the target device which
       is currently stored on the source device. If the source device is
       not available anymore, or if the -r option is set, the data is
       built only using the RAID redundancy mechanisms. After completion
       of the operation, the source device is removed from the filesystem.
       If the <srcdev> is a numerical value, it is assumed to be the
       device id of the filesystem which is mounted at <path>, otherwise
       is is the path to the source device. If the source device is
       disconnected, from the system, you have to use the devid parameter
       format. The <targetdev> needs to be same size or larger than the

           the filesystem has to be resized to fully take advantage of a
           larger target device, this can be achieved with btrfs
           filesystem resize <devid>:max /path

           only read from <srcdev> if no other zero-defect mirror exists.
           (enable this if your drive has lots of read errors, the access
           would be very slow)

           force using and overwriting <targetdev> even if it looks like
           containing a valid btrfs filesystem.

           A valid filesystem is assumed if a btrfs superblock is found
           which contains a correct checksum. Devices which are currently
           mounted are never allowed to be used as the <targetdev>.

           no background replace.

   status [-1] <mount_point>
       Print status and progress information of a running device replace


           print once instead of print continuously until the replace
           operation finishes (or is cancelled)


   btrfs replace returns a zero exit status if it succeeds. Non zero is
   returned in case of failure.


   btrfs is part of btrfs-progs. Please refer to the btrfs wiki for further details.


   mkfs.btrfs(8), btrfs-device(8),


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