восстановить файловую систему XFS (repair an XFS filesystem)
Статус выхода (Exit)
xfs_repair -n (no modify mode) will return a status of 1 if
filesystem corruption was detected and 0 if no filesystem
corruption was detected. xfs_repair run without the -n option
will always return a status code of 0 if it completes without
problems, unless the flag -e is used. If it is used, then status
4 is reported when any issue with the filesystem was found, but
could be fixed. If a runtime error is encountered during
operation, it will return a status of 1. In this case, xfs_repair
should be restarted. If xfs_repair is unable to proceed due to a
dirty log, it will return a status of 2. See below.