XFS Dump

    https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7...

    Backup of " / " {root} directory:

     /boot - 1GB - xfs  __standard_partition
    My scenario/home - 1GB - xfs ___lvm
     / - 32GB - xfs  ___lvm
    • mkdir /rescue_disk && mkdir /rescue_disk/backups && mkdir /rescue_disk/xfsdump
    •  chmod 700 /rescue_disk/backups &&  chmod 700 /rescue_disk/xfsdump
    • cd /rescue_disk/backups
    • df -hv
      Filesystem                Size  Used Avail Use% Mounted on
      /dev/mapper/centos7-root   31G  4.1G   27G  13% /
      devtmpfs                  907M     0  907M   0% /dev
      tmpfs                     920M     0  920M   0% /dev/shm
      tmpfs                     920M  8.7M  911M   1% /run
      tmpfs                     920M     0  920M   0% /sys/fs/cgroup
      /dev/mapper/centos7-home  953M   42M  912M   5% /home
      /dev/vda1                 950M  183M  768M  20% /boot
      tmpfs                     184M     0  184M   0% /run/user/0
    • lsblk
      NAME                       MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
      vda                        252:0    0   50G  0 disk
      ├─vda1                     252:1    0  953M  0 part /boot
      └─vda2                     252:2    0 47.1G  0 part
        ├─centos7-lv_cache_cdata 253:0    0 12.1G  0 lvm
        │ └─centos7-root         253:3    0   31G  0 lvm  /
        ├─centos7-lv_cache_cmeta 253:1    0   28M  0 lvm
        │ └─centos7-root         253:3    0   31G  0 lvm  /
        ├─centos7-root_corig     253:2    0   31G  0 lvm
        │ └─centos7-root         253:3    0   31G  0 lvm  /
        ├─centos7-swap           253:4    0  2.9G  0 lvm  [SWAP]
        └─centos7-home           253:5    0  956M  0 lvm  /home
    • additional backup of boot-system:
      tar czf boot.tar.gz /boot
      mysqldump -u root -p isp3_cpanel > isp3_cpanel.sql
      mysqldump -u root -p webmail >  webmail.sql


       
    •  xfsdump  -f /rescue_disk/xfsdump/root.xfsdump /
      xfsdump: using file dump (drive_simple) strategy
      xfsdump: version 3.1.7 (dump format 3.0) - type ^C for status and control
       ============================= dump label dialog ==============================
      please enter label for this dump session (timeout in 300 sec)
       -> root_backup
      session label entered: "root_backup"
       --------------------------------- end dialog ---------------------------------
      xfsdump: saving user quota information for: /
      xfsdump: saving group quota information for: /
      xfsdump: level 0 dump of website.development.hk:/
      xfsdump: dump date: Mon Apr  1 22:44:45 2019
      xfsdump: session id: 9200bb8a-cde1-4b41-b4d5-7a6818ae5423
      xfsdump: session label: "root_backup"
      xfsdump: ino map phase 1: constructing initial dump list
      xfsdump: ino map phase 2: skipping (no pruning necessary)
      xfsdump: ino map phase 3: skipping (only one dump stream)
      xfsdump: ino map construction complete
      xfsdump: estimated dump size: 4370714176 bytes
      xfsdump: /var/lib/xfsdump/inventory created
       ============================= media label dialog =============================
      please enter label for media in drive 0 (timeout in 300 sec)
       -> centos7
      media label entered: "centos7"
       --------------------------------- end dialog ---------------------------------
      xfsdump: creating dump session media file 0 (media 0, file 0)
      xfsdump: dumping ino map
      xfsdump: dumping directories
      xfsdump: dumping non-directory files
      xfsdump: ending media file
      xfsdump: media file size 5604529112 bytes
      xfsdump: dump size (non-dir files) : 5526097992 bytes
      xfsdump: dump complete: 93 seconds elapsed
      xfsdump: Dump Summary:
      xfsdump:   stream 0 /rescue_disk/xfsdump/root.xfsdump OK (success)
      xfsdump: Dump Status: SUCCESS
       --total_backup_takes_less_than_minute--
    • xfsdump -l 0  -f /rescue_disk/xfsdump/home.xfsdump /home

    • xfsdump -l 0  -f  /rescue_disk/xfsdump/boot.xfsdump /boot


      RECOVERY

    • xfsrestore -f /rescue_disk/xfsdump/root.xfsdump /
       

    additional tips: (database recovery)

    systemctl stop mysql
    mysql -u root -p database_name < database_name.sql
    chown -R mysql:mysql /var/lib/mysql
    systemctl restart mysql

    Documentation

     

    3.6. Suspending an XFS File System

    To suspend or resume write activity to a file system, use the following command:
    xfs_freeze mount-point
    Suspending write activity allows hardware-based device snapshots to be used to capture the file system in a consistent state.

    Note

    The xfs_freeze utility is provided by the xfsprogs package, which is only available on x86_64.
    To suspend (that is, freeze) an XFS file system, use:
    xfs_freeze -f /mount/point
    To unfreeze an XFS file system, use:xfs_freeze -u /mount/point
    When taking an LVM snapshot, it is not necessary to use xfs_freeze to suspend the file system first. Rather, the LVM management tools will automatically suspend the XFS file system before taking the snapshot.
    For more information about freezing and unfreezing an XFS file system, see man xfs_freeze

    3.7. Backing Up and Restoring XFS File Systems

    XFS file system backup and restoration involve these utilities:
    • xfsdump for creating the backup
    • xfsrestore for restoring from backup

    3.7.1. Features of XFS Backup and Restoration

    Backup

    You can use the xfsdump utility to:
    • Perform backups to regular file images.
      Only one backup can be written to a regular file.
    • Perform backups to tape drives.
      The xfsdump utility also allows you to write multiple backups to the same tape. A backup can span multiple tapes.
      To back up multiple file systems to a single tape device, simply write the backup to a tape that already contains an XFS backup. This appends the new backup to the previous one. By default, xfsdump never overwrites existing backups.
    • Create incremental backups.
      The xfsdump utility uses dump levels to determine a base backup to which other backups are relative. Numbers from 0 to 9 refer to increasing dump levels. An incremental backup only backs up files that have changed since the last dump of a lower level:
      • To perform a full backup, perform a level 0 dump on the file system.
      • A level 1 dump is the first incremental backup after a full backup. The next incremental backup would be level 2, which only backs up files that have changed since the last level 1 dump; and so on, to a maximum of level 9.
    • Exclude files from a backup using size, subtree, or inode flags to filter them.

    Restoration

    The xfsrestore utility restores file systems from backups produced by xfsdump. The xfsrestore utility has two modes:
    • The simple mode enables users to restore an entire file system from a level 0 dump. This is the default mode.
    • The cumulative mode enables file system restoration from an incremental backup: that is, level 1 to level 9.
    A unique session ID or session label identifies each backup. Restoring a backup from a tape containing multiple backups requires its corresponding session ID or label.
    To extract, add, or delete specific files from a backup, enter the xfsrestore interactive mode. The interactive mode provides a set of commands to manipulate the backup files.

    3.7.2. Backing Up an XFS File System

    This procedure describes how to back up the content of an XFS file system into a file or a tape.

    Procedure 3.1. Backing Up an XFS File System

    • Use the following command to back up an XFS file system:
      xfsdump -l level [-L label] -f backup-destination path-to-xfs-filesystem
      • Replace level with the dump level of your backup. Use 0 to perform a full backup or 1 to 9 to perform consequent incremental backups.
      • Replace backup-destination with the path where you want to store your backup. The destination can be a regular file, a tape drive, or a remote tape device. For example, /backup-files/Data.xfsdump for a file or /dev/st0 for a tape drive.
      • Replace path-to-xfs-filesystem with the mount point of the XFS file system you want to back up. For example, /mnt/data/. The file system must be mounted.
      • When backing up multiple file systems and saving them on a single tape device, add a session label to each backup using the -L label option so that it is easier to identify them when restoring. Replace label with any name for your backup: for example, backup_data.

    Example 3.4. Backing up Multiple XFS File Systems

    • To back up the content of XFS file systems mounted on the /boot/ and /data/ directories and save them as files in the /backup-files/ directory:xfsdump -l 0 -f /backup-files/boot.xfsdump /boot xfsdump -l 0 -f /backup-files/data.xfsdump /data
    • To back up multiple file systems on a single tape device, add a session label to each backup using the -L label option:
      xfsdump -l 0 -L "backup_boot" -f /dev/st0 /boot
xfsdump -l 0 -L "backup_data" -f /dev/st0 /data

    Additional Resources

    • For more information about backing up XFS file systems, see the xfsdump(8) man page.

    3.7.3. Restoring an XFS File System from Backup

    This procedure describes how to restore the content of an XFS file system from a file or tape backup.

    Prerequisites

    Procedure 3.2. Restoring an XFS File System from Backup

    • The command to restore the backup varies depending on whether you are restoring from a full backup or an incremental one, or are restoring multiple backups from a single tape device:
      xfsrestore [-r] [-S session-id] [-L session-label] [-i]
             -f backup-location restoration-path
      • Replace backup-location with the location of the backup. This can be a regular file, a tape drive, or a remote tape device. For example, /backup-files/Data.xfsdump for a file or /dev/st0 for a tape drive.
      • Replace restoration-path with the path to the directory where you want to restore the file system. For example, /mnt/data/.
      • To restore a file system from an incremental (level 1 to level 9) backup, add the -r option.
      • To restore a backup from a tape device that contains multiple backups, specify the backup using the -S or -L options.
        The -S lets you choose a backup by its session ID, while the -L lets you choose by the session label. To obtain the session ID and session labels, use the xfsrestore -I command.
        Replace session-id with the session ID of the backup. For example, b74a3586-e52e-4a4a-8775-c3334fa8ea2c. Replace session-label with the session label of the backup. For example, my_backup_session_label.
      • To use xfsrestore interactively, use the -i option.
        The interactive dialog begins after xfsrestore finishes reading the specified device. Available commands in the interactive xfsrestore shell include cd, ls, add, delete, and extract; for a complete list of commands, use the help command.

    Example 3.5. Restoring Multiple XFS File Systems

    To restore the XFS backup files and save their content into directories under /mnt/:
    xfsrestore -f /backup-files/boot.xfsdump /mnt/boot/
xfsrestore -f /backup-files/data.xfsdump /mnt/data/
    To restore from a tape device containing multiple backups, specify each backup by its session label or session ID:
    xfsrestore -f /dev/st0 -L "backup_boot" /mnt/boot/
xfsrestore -f /dev/st0 -S "45e9af35-efd2-4244-87bc-4762e476cbab" /mnt/data/

    Informational Messages When Restoring a Backup from a Tape

    When restoring a backup from a tape with backups from multiple file systems, the xfsrestore utility might issue messages. The messages inform you whether a match of the requested backup has been found when xfsrestore examines each backup on the tape in sequential order. For example:
    xfsrestore: preparing drive
xfsrestore: examining media file 0
xfsrestore: inventory session uuid (8590224e-3c93-469c-a311-fc8f23029b2a) does not match the media header's session uuid (7eda9f86-f1e9-4dfd-b1d4-c50467912408)
xfsrestore: examining media file 1
xfsrestore: inventory session uuid (8590224e-3c93-469c-a311-fc8f23029b2a) does not match the media header's session uuid (7eda9f86-f1e9-4dfd-b1d4-c50467912408)
[...]
    The informational messages keep appearing until the matching backup is found.

    Additional Resources

    • For more information about restoring XFS file systems, see the xfsrestore(8) man page.

    3.9. Other XFS File System Utilities

    Red Hat Enterprise Linux 7 also features other utilities for managing XFS file systems:
    xfs_fsr
    Used to defragment mounted XFS file systems. When invoked with no arguments, xfs_fsr defragments all regular files in all mounted XFS file systems. This utility also allows users to suspend a defragmentation at a specified time and resume from where it left off later.
    In addition, xfs_fsr also allows the defragmentation of only one file, as in xfs_fsr /path/to/file. Red Hat advises not to periodically defrag an entire file system because XFS avoids fragmentation by default. System wide defragmentation could cause the side effect of fragmentation in free space.
    xfs_bmap
    Prints the map of disk blocks used by files in an XFS filesystem. This map lists each extent used by a specified file, as well as regions in the file with no corresponding blocks (that is, holes).
    xfs_info
    Prints XFS file system information.
    xfs_admin
    Changes the parameters of an XFS file system. The xfs_admin utility can only modify parameters of unmounted devices or file systems.
    xfs_copy
    Copies the contents of an entire XFS file system to one or more targets in parallel.
    The following utilities are also useful in debugging and analyzing XFS file systems:
    xfs_metadump
    Copies XFS file system metadata to a file. Red Hat only supports using the xfs_metadump utility to copy unmounted file systems or read-only mounted file systems; otherwise, generated dumps could be corrupted or inconsistent.
    xfs_mdrestore
    Restores an XFS metadump image (generated using xfs_metadump) to a file system image.
    xfs_db
    Debugs an XFS file system.
    For more information about these utilities, see their respective man pages.

    Live experience

    xfs_info /

    meta-data=/dev/mapper/centos7-root isize=512    agcount=4, agsize=732416 blks
             =                       sectsz=512   attr=2, projid32bit=1
             =                       crc=1        finobt=0 spinodes=0
    data     =                       bsize=4096   blocks=2929664, imaxpct=25
             =                       sunit=0      swidth=0 blks
    naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
    log      =internal               bsize=4096   blocks=2560, version=2
             =                       sectsz=512   sunit=0 blks, lazy-count=1
    realtime =none                   extsz=4096   blocks=0, rtextents=0

    yum install xfsdump

    xfs_freeze -f /

    ]# xfsdump -l 0 -f /storage_data/dump_area/root.xfsdump /

    xfsdump: using file dump (drive_simple) strategy
    xfsdump: version 3.1.7 (dump format 3.0) - type ^C for status and control

     ============================= dump label dialog ==============================

    please enter label for this dump session (timeout in 300 sec)
     -> rootdump
    session label entered: "rootdump"

     --------------------------------- end dialog ---------------------------------

    xfsdump: level 0 dump of 94-237-72-121.sg-sin1.upcloud.host:/
    xfsdump: dump date: Sat Mar 30 17:28:47 2019
    xfsdump: session id: d69f486f-d291-4785-bf5a-c5c5e4483d73
    xfsdump: session label: "rootdump"
    xfsdump: ino map phase 1: constructing initial dump list
    xfsdump: ino map phase 2: skipping (no pruning necessary)
    xfsdump: ino map phase 3: skipping (only one dump stream)
    xfsdump: ino map construction complete
    xfsdump: estimated dump size: 1037686144 bytes
    xfsdump: /var/lib/xfsdump/inventory created

     ============================= media label dialog =============================

    please enter label for media in drive 0 (timeout in 300 sec)
     -> mediarootdump
    media label entered: "mediarootdump"

     --------------------------------- end dialog ---------------------------------

    xfsdump: creating dump session media file 0 (media 0, file 0)
    xfsdump: dumping ino map
    xfsdump: dumping directories
    xfsdump: dumping non-directory files
    xfsdump: ending media file
    xfsdump: media file size 1007555104 bytes
    xfsdump: dump size (non-dir files) : 990488744 bytes
    xfsdump: dump complete: 141 seconds elapsed
    xfsdump: Dump Summary:
    xfsdump:   stream 0 /storage_data/dump_area/root.xfsdump OK (success)
    xfsdump: Dump Status: SUCCESS

    xfs_freeze -u /

    Tags: 
    xfs, centos, redhat, backup, dump