Sun Cluster System Administration Guide for Solaris OS

Backing Up a Cluster

Table 12–1 Task Map: Backing Up Cluster Files

Task 

Instructions 

Find the names of the file systems you want to back up 

How to Find File System Names to Back Up

Calculate how many tapes you need to contain a full backup 

How to Determine the Number of Tapes Needed for a Full Backup

Back up the root file system 

How to Back Up the Root (/) File System

Perform online backup for mirrored or plexed file systems 

How to Perform Online Backups for Mirrors (Solaris Volume Manager)

 

How to Perform Online Backups for Volumes (Veritas Volume Manager)

Back up the cluster configuration 

How to Back Up the Cluster Configuration

Back up disk partitioning configuration for storage disk 

See the documentation for your storage disk 

ProcedureHow to Find File System Names to Back Up

Use this procedure to determine the names of the file systems that you want to back up.

  1. Display the contents of the /etc/vfstab file.

    You do not need to be superuser or assume an equivalent role to run this command.


    # more /etc/vfstab
    
  2. Look in the mount-point column for the name of the file system that you are backing up.

    Use this name when you back up the file system.


    # more /etc/vfstab 
    

Example 12–1 Finding File System Names to Back Up

The following example displays the names of available file systems that are listed in the /etc/vfstab file.


# more /etc/vfstab
#device             device             mount  FS fsck  mount  mount
#to mount           to fsck            point  type     pass   at boot  options
#
#/dev/dsk/c1d0s2    /dev/rdsk/c1d0s2   /usr     ufs     1      yes      -
 f                  -                  /dev/fd  fd      -      no       -
 /proc              -                  /proc    proc    -      no       -
 /dev/dsk/c1t6d0s1  -                  -        swap    -      no       -
 /dev/dsk/c1t6d0s0  /dev/rdsk/c1t6d0s0 /        ufs     1      no       -
 /dev/dsk/c1t6d0s3  /dev/rdsk/c1t6d0s3 /cache   ufs     2      yes      -
 swap               -                  /tmp     tmpfs   -      yes      -

ProcedureHow to Determine the Number of Tapes Needed for a Full Backup

Use this procedure to calculate the number of tapes that you need to back up a file system.

  1. Become superuser or assume an equivalent role on the cluster node that you are backing up.

  2. Estimate the size of the backup in bytes.


    # ufsdump S filesystem 
    
    S

    Displays the estimated number of bytes needed to perform the backup.

    filesystem

    Specifies the name of the file system you want to back up.

  3. Divide the estimated size by the capacity of the tape to see how many tapes you need.


Example 12–2 Determining the Number of Tapes Needed

In the following example, the file system size of 905,881,620 bytes easily fits on a 4-Gbyte tape (905,881,620 ÷ 4,000,000,000).


# ufsdump S /global/phys-schost-1
905881620

ProcedureHow to Back Up the Root (/) File System

Use this procedure to back up the root (/) file system of a cluster node. Ensure that the cluster is running without errors before performing the backup procedure.

The phys-schost# prompt reflects a global-cluster prompt. Perform this procedure on a global cluster.

This procedure provides the long forms of the Sun Cluster commands. Most commands also have short forms. Except for the long and short forms of the command names, the commands are identical. For a list of the commands and their short forms, see Appendix B, Sun Cluster Object-Oriented Commands.

  1. Become superuser or assume a role that provides solaris.cluster.modify RBAC authorization on the cluster node that you are backing up.

  2. Switch each running data service from the node to be backed up to another node in the cluster.


    # clnode evacuate node
    
    node

    Specifies the node from which you are switching resource groups and device groups.

  3. Shut down the node.


    # shutdown -g0 -y -i0
    
  4. Reboot the node in noncluster mode.

    • On SPARC based systems, run the following command.


      ok boot -xs
      
    • On x86 based systems, run the following commands.


      phys-schost# shutdown -g -y -i0
      
      Press any key to continue
    1. In the GRUB menu, use the arrow keys to select the appropriate Solaris entry and type e to edit its commands.

      The GRUB menu appears similar to the following:


      GNU GRUB version 0.95 (631K lower / 2095488K upper memory)
      +-------------------------------------------------------------------------+
      | Solaris 10 /sol_10_x86                                                  |
      | Solaris failsafe                                                        |
      |                                                                         |
      +-------------------------------------------------------------------------+
      Use the ^ and v keys to select which entry is highlighted.
      Press enter to boot the selected OS, 'e' to edit the
      commands before booting, or 'c' for a command-line.

      For more information about GRUB based booting, see Booting an x86 Based System by Using GRUB (Task Map) in System Administration Guide: Basic Administration.

    2. In the boot parameters screen, use the arrow keys to select the kernel entry and type e to edit the entry.

      The GRUB boot parameters screen appears similar to the following:


      GNU GRUB version 0.95 (615K lower / 2095552K upper memory)
      +----------------------------------------------------------------------+
      | root (hd0,0,a)                                                       |
      | kernel /platform/i86pc/multiboot                                     |
      | module /platform/i86pc/boot_archive                                  |
      +----------------------------------------------------------------------+
      Use the ^ and v keys to select which entry is highlighted.
      Press 'b' to boot, 'e' to edit the selected command in the
      boot sequence, 'c' for a command-line, 'o' to open a new line
      after ('O' for before) the selected line, 'd' to remove the
      selected line, or escape to go back to the main menu.
    3. Add -x to the command to specify that the system boot into noncluster mode.


      [ Minimal BASH-like line editing is supported. For the first word, TAB
      lists possible command completions. Anywhere else TAB lists the possible
      completions of a device/filename. ESC at any time exits. ]
      
      grub edit> kernel /platform/i86pc/multiboot -x
    4. Press the Enter key to accept the change and return to the boot parameters screen.

      The screen displays the edited command.


      GNU GRUB version 0.95 (615K lower / 2095552K upper memory)
      +----------------------------------------------------------------------+
      | root (hd0,0,a)                                                       |
      | kernel /platform/i86pc/multiboot -x                                  |
      | module /platform/i86pc/boot_archive                                  |
      +----------------------------------------------------------------------+
      Use the ^ and v keys to select which entry is highlighted.
      Press 'b' to boot, 'e' to edit the selected command in the
      boot sequence, 'c' for a command-line, 'o' to open a new line
      after ('O' for before) the selected line, 'd' to remove the
      selected line, or escape to go back to the main menu.-
    5. Type b to boot the node into noncluster mode.


      Note –

      This change to the kernel boot parameter command does not persist over the system boot. The next time you reboot the node, it will boot into cluster mode. To boot into noncluster mode instead, perform these steps to again to add the -x option to the kernel boot parameter command.


  5. Back up the root (/) file system by creating a UFS snapshot.

    1. Make sure the file system has enough disk space for the backing-store file.


      # df -k
      
    2. Make sure that a backing-store file of the same name and location does not already exist.


      # ls /backing-store-file
      
    3. Create the UFS snapshot.


      # fssnap -F ufs -o bs=/backing-store-file /file-system
      
    4. Verify that the snapshot has been created.


      # /usr/lib/fs/ufs/fssnap -i /file-system
      
  6. Reboot the node in cluster mode.


    # init 6
    

Example 12–3 Backing Up the Root (/) File System

In the following example, a snapshot of the root (/) file system is saved to /scratch/usr.back.file in the /usr directory. `


# fssnap -F ufs -o bs=/scratch/usr.back.file /usr
  /dev/fssnap/1

ProcedureHow to Perform Online Backups for Mirrors (Solaris Volume Manager)

A mirrored Solstice DiskSuite metadevice or Solaris Volume Manager volume can be backed up without unmounting it or taking the entire mirror offline. One of the submirrors must be taken offline temporarily, thus losing mirroring, but it can be placed online and resynchronized as soon as the backup is complete, without halting the system or denying user access to the data. Using mirrors to perform online backups creates a backup that is a “snapshot” of an active file system.

A problem might occur if a program writes data onto the volume immediately before the lockfs command is run. To prevent this problem, temporarily stop all the services running on this node. Also, ensure the cluster is running without errors before performing the backup procedure.

The phys-schost# prompt reflects a global-cluster prompt. Perform this procedure on a global cluster.

This procedure provides the long forms of the Sun Cluster commands. Most commands also have short forms. Except for the long and short forms of the command names, the commands are identical. For a list of the commands and their short forms, see Appendix B, Sun Cluster Object-Oriented Commands.

  1. Become superuser or assume an equivalent role on the cluster node that you are backing up.

  2. Use the metaset(1M) command to determine which node has the ownership on the backed-up volume.


    # metaset -s setname
    
    -s setname

    Specifies the disk set name.

  3. Use the lockfs(1M) command with the -w option to lock the file system from writes.


    # lockfs -w mountpoint 
    

    Note –

    You must lock the file system only if a UFS file system resides on the mirror. For example, if the Solstice DiskSuite metadevice or Solaris Volume Manager volume is set up as a raw device for database management software or some other specific application, you do not need to use the lockfs command. You might, however, run the appropriate vendor-dependent utility to flush any buffers and lock access.


  4. Use the metastat(1M) command to determine the names of the submirrors.


    # metastat -s setname -p
    
    -p

    Displays the status in a format similar to the md.tab file.

  5. Use the metadetach(1M) command to take one submirror offline from the mirror.


    # metadetach -s setname mirror submirror
    

    Note –

    Reads continue to be made from the other submirrors. However, the offline submirror is unsynchronized as soon as the first write is made to the mirror. This inconsistency is corrected when the offline submirror is brought back online. You do not need to run fsck.


  6. Unlock the file systems and allow writes to continue, using the lockfs command with the -u option.


    # lockfs -u mountpoint 
    
  7. Perform a file system check.


    # fsck /dev/md/diskset/rdsk/submirror
    
  8. Back up the offline submirror to tape or another medium.

    Use the ufsdump(1M) command or the backup utility that you usually use.


    # ufsdump 0ucf dump-device submirror
    

    Note –

    Use the raw device (/rdsk) name for the submirror, rather than the block device (/dsk) name.


  9. Use the metattach(1M) command to place the metadevice or volume back online.


    # metattach -s setname mirror submirror
    

    When the metadevice or volume is placed online, it is automatically resynchronized with the mirror.

  10. Use the metastat command to verify that the submirror is resynchronizing.


    # metastat -s setname mirror
    

Example 12–4 Performing Online Backups for Mirrors (Solaris Volume Manager)

In the following example, the cluster node phys-schost-1 is the owner of the metaset schost-1, therefore the backup procedure is performed from phys-schost-1. The mirror /dev/md/schost-1/dsk/d0 consists of the submirrors d10 , d20, and d30.


[Determine the owner of the metaset:]
# metaset -s schost-1
Set name = schost-1, Set number = 1
Host                Owner
  phys-schost-1     Yes 
...
[Lock the file system from writes:] 
# lockfs -w /global/schost-1
[List the submirrors:]
# metastat -s schost-1 -p
schost-1/d0 -m schost-1/d10 schost-1/d20 schost-1/d30 1
schost-1/d10 1 1 d4s0
schost-1/d20 1 1 d6s0
schost-1/d30 1 1 d8s0
[Take a submirror offline:]
# metadetach -s schost-1 d0 d30
[Unlock the file system:]
# lockfs -u /
[Check the file system:]
# fsck /dev/md/schost-1/rdsk/d30
[Copy the submirror to the backup device:]
# ufsdump 0ucf /dev/rmt/0 /dev/md/schost-1/rdsk/d30
  DUMP: Writing 63 Kilobyte records
  DUMP: Date of this level 0 dump: Tue Apr 25 16:15:51 2000
  DUMP: Date of last level 0 dump: the epoch
  DUMP: Dumping /dev/md/schost-1/rdsk/d30 to /dev/rdsk/c1t9d0s0.
  ...
  DUMP: DUMP IS DONE
[Bring the submirror back online:]
# metattach -s schost-1 d0 d30
schost-1/d0: submirror schost-1/d30 is attached
[Resynchronize the submirror:]
# metastat -s schost-1 d0
schost-1/d0: Mirror
    Submirror 0: schost-0/d10
      State: Okay         
    Submirror 1: schost-0/d20
      State: Okay
    Submirror 2: schost-0/d30
      State: Resyncing
    Resync in progress: 42% done
    Pass: 1
    Read option: roundrobin (default)
...

ProcedureHow to Perform Online Backups for Volumes (Veritas Volume Manager)

Veritas Volume Manager identifies a mirrored volume as a plex. A plex can be backed up without unmounting it or taking the entire volume offline. This result is accomplished by creating a snapshot copy of the volume and backing up this temporary volume without halting the system or denying user access to the data.

Ensure that the cluster is running without errors before performing the backup procedure.

The phys-schost# prompt reflects a global-cluster prompt. Perform this procedure on a global cluster.

This procedure provides the long forms of the Sun Cluster commands. Most commands also have short forms. Except for the long and short forms of the command names, the commands are identical. For a list of the commands and their short forms, see Appendix B, Sun Cluster Object-Oriented Commands.

  1. Log on to any node in the cluster, and become superuser or assume a role that provides solaris.cluster.admin RBAC authorization on the current primary node for the disk group on the cluster.

  2. List the disk group information.


    # vxprint -g diskgroup
    
  3. Determine which node has the disk group currently imported, indicating it is the primary node for the disk group.


    # cldevicegroup status
    
  4. Create a snapshot of the volume.


    # vxassist -g diskgroup snapstart volume
    

    Note –

    Creating a snapshot can take a long time, depending on the size of your volume.


  5. Verify that the new volume was created.


    # vxprint -g diskgroup
    

    When the snapshot is complete, a status of Snapdone displays in the State field for the selected disk group.

  6. Stop any data services that are accessing the file system.


    # clresourcegroup offline resource-group
    

    Note –

    Stop all data services to ensure that the data file system is properly backed up. If no data services are running, you do not need to perform Step 6 and Step 8.


  7. Create a backup volume named bkup-vol and attach the snapshot volume to it.


    # vxassist -g diskgroup snapshot volume bkup-vol
    
  8. Restart any data services that were stopped in Step 6, using the clresourcegroup command.


    # clresourcegroup online - zone -n node resourcegroup
    
    node

    The name of the node.

    zone

    The name of the global-cluster non-voting node (node) that can master the resource group. Specify zone only if you specified a non-voting node when you created the resource group.

  9. Verify the volume is now attached to the new volume bkup-vol.


    # vxprint -g diskgroup
    
  10. Register the device group configuration change.


    # cldevicegroup sync diskgroup
    
  11. Check the backup volume.


    # fsck -y /dev/vx/rdsk/diskgroup/bkup-vol
    
  12. Perform a backup to copy the volume bkup-vol to tape or another medium.

    Use the ufsdump(1M) command or the backup utility that you normally use.


    # ufsdump 0ucf dump-device /dev/vx/dsk/diskgroup/bkup-vol
    
  13. Remove the temporary volume.


    # vxedit -rf rm bkup-vol
    
  14. Register the disk group configuration changes.


    # cldevicegroup sync diskgroup
    

Example 12–5 Performing Online Backups for Volumes (Veritas Volume Manager)

In the following example, the cluster node phys-schost-2 is the primary owner of the device group schost-1. Therefore, the backup procedure is performed from phys-schost-2. The volume /vo101 is copied and then associated with a new volume, bkup-vol.


[Become superuser or assume a role that provides solaris.cluster.admin RBAC authorization on 
the primary node.]
[Identify the current primary node for the device group:]
# cldevicegroup status
-- Device Group Servers --
                         Device Group     Primary           Secondary
                         ------------     -------           ---------
 Device group servers:   rmt/1            -                 -
 Device group servers:   schost-1         phys-schost-2     phys-schost-1

-- Device Group Status --
                             Device Group        Status              
                             ------------        ------              
 Device group status:        rmt/1               Offline
 Device group status:        schost-1            Online
[List the device group information:]
# vxprint -g schost-1
TY NAME            ASSOC     KSTATE   LENGTH   PLOFFS STATE   TUTIL0  PUTIL0
dg schost-1       schost-1   -        -        -      -        -      -
  
dm schost-101     c1t1d0s2   -        17678493 -      -        -      -
dm schost-102     c1t2d0s2   -        17678493 -      -        -      -
dm schost-103     c2t1d0s2   -        8378640  -      -        -      -
dm schost-104     c2t2d0s2   -        17678493 -      -        -      -
dm schost-105     c1t3d0s2   -        17678493 -      -        -      -
dm schost-106     c2t3d0s2   -        17678493 -      -        -      -
 
v  vol01          gen        ENABLED  204800   -      ACTIVE   -      -
pl vol01-01       vol01      ENABLED  208331   -      ACTIVE   -      -
sd schost-101-01  vol01-01   ENABLED  104139   0      -        -      -
sd schost-102-01  vol01-01   ENABLED  104139   0      -        -      -
pl vol01-02       vol01      ENABLED  208331   -      ACTIVE   -      -
sd schost-103-01  vol01-02   ENABLED  103680   0      -        -      -
sd schost-104-01  vol01-02   ENABLED  104139   0      -        -      -
pl vol01-03       vol01      ENABLED  LOGONLY  -      ACTIVE   -      -
sd schost-103-02  vol01-03   ENABLED  5        LOG    -        -      -
[Start the snapshot operation:]
# vxassist -g schost-1 snapstart vol01
[Verify the new volume was created:]
# vxprint -g schost-1
TY NAME            ASSOC    KSTATE    LENGTH   PLOFFS STATE   TUTIL0  PUTIL0
dg schost-1       schost-1   -        -        -      -        -      -
  
dm schost-101     c1t1d0s2   -        17678493 -      -        -      -
dm schost-102     c1t2d0s2   -        17678493 -      -        -      -
dm schost-103     c2t1d0s2   -        8378640  -      -        -      -
dm schost-104     c2t2d0s2   -        17678493 -      -        -      -
dm schost-105     c1t3d0s2   -        17678493 -      -        -      -
dm schost-106     c2t3d0s2   -        17678493 -      -        -      -
  
v  vol01          gen        ENABLED  204800   -      ACTIVE   -      -
pl vol01-01       vol01      ENABLED  208331   -      ACTIVE   -      -
sd schost-101-01  vol01-01   ENABLED  104139   0      -        -      -
sd schost-102-01  vol01-01   ENABLED  104139   0      -        -      -
pl vol01-02       vol01      ENABLED  208331   -      ACTIVE   -      -
sd schost-103-01  vol01-02   ENABLED  103680   0      -        -      -
sd schost-104-01  vol01-02   ENABLED  104139   0      -        -      -
pl vol01-03       vol01      ENABLED  LOGONLY  -      ACTIVE   -      -
sd schost-103-02  vol01-03   ENABLED  5        LOG    -        -      -
pl vol01-04       vol01      ENABLED  208331   -      SNAPDONE -      -
sd schost-105-01  vol01-04   ENABLED  104139   0      -        -      -
sd schost-106-01  vol01-04   ENABLED  104139   0      -        -      -
[Stop data services, if necessary:]
# clresourcegroup offline nfs-rg
[Create a copy of the volume:]
# vxassist -g schost-1 snapshot vol01 bkup-vol
[Restart data services, if necessary:]
# clresourcegroup online -n phys-schost-1 nfs-rg
[Verify bkup-vol was created:]
# vxprint -g schost-1
TY NAME           ASSOC       KSTATE   LENGTH   PLOFFS STATE   TUTIL0  PUTIL0
dg schost-1       schost-1    -        -        -      -        -      -
 
dm schost-101     c1t1d0s2    -        17678493 -      -        -      -
...
 
v  bkup-vol       gen         ENABLED  204800   -      ACTIVE   -      -
pl bkup-vol-01    bkup-vol    ENABLED  208331   -      ACTIVE   -      -
sd schost-105-01  bkup-vol-01 ENABLED  104139   0      -        -      -
sd schost-106-01  bkup-vol-01 ENABLED  104139   0      -        -      -
 
v  vol01          gen         ENABLED  204800   -      ACTIVE   -      -
pl vol01-01       vol01       ENABLED  208331   -      ACTIVE   -      -
sd schost-101-01  vol01-01    ENABLED  104139   0      -        -      -
sd schost-102-01  vol01-01    ENABLED  104139   0      -        -      -
pl vol01-02       vol01       ENABLED  208331   -      ACTIVE   -      -
sd schost-103-01  vol01-02    ENABLED  103680   0      -        -      -
sd schost-104-01  vol01-02    ENABLED  104139   0      -        -      -
pl vol01-03       vol01       ENABLED  LOGONLY  -      ACTIVE   -      -
sd schost-103-02  vol01-03    ENABLED  5        LOG    -        -      -
[Synchronize the disk group with cluster framework:]
# cldevicegroup sync schost-1
[Check the file systems:]
# fsck -y /dev/vx/rdsk/schost-1/bkup-vol
[Copy bkup-vol to the backup device:]
# ufsdump 0ucf /dev/rmt/0 /dev/vx/rdsk/schost-1/bkup-vol
  DUMP: Writing 63 Kilobyte records
  DUMP: Date of this level 0 dump: Tue Apr 25 16:15:51 2000
  DUMP: Date of last level 0 dump: the epoch
  DUMP: Dumping /dev/vx/dsk/schost-2/bkup-vol to /dev/rmt/0.
  ...
  DUMP: DUMP IS DONE
[Remove the bkup-volume:]
# vxedit -rf rm bkup-vol
[Synchronize the disk group:]
# cldevicegroup sync schost-1

ProcedureHow to Back Up the Cluster Configuration

To ensure that your cluster configuration is archived and to facilitate easy recovery of the your cluster configuration, periodically back up your cluster configuration. Sun Cluster 3.2 provides the ability to export your cluster configuration to an eXtensible Markup Language (XML) file.

  1. Log on to any node in the cluster, and become superuser or assume a role that provides solaris.cluster.read RBAC authorization.

  2. Export the cluster configuration information to a file.


    # /usr/cluster/bin/cluster export -o configfile
    
    configfile

    The name of the XML configuration file that the cluster command is exporting the cluster configuration information to. For information about the XML configuration file, see clconfiguration(5CL)

  3. Verify that the cluster configuration information was successfully exported to the XML file.


    # vi configfile