Storage Foundation 7.4.1 Administrator's Guide - Linux
- Section I. Introducing Storage Foundation
- Overview of Storage Foundation
- How Dynamic Multi-Pathing works
- How Veritas Volume Manager works
- How Veritas Volume Manager works with the operating system
- How Veritas Volume Manager handles storage management
- Volume layouts in Veritas Volume Manager
- Online relayout
- Volume resynchronization
- Dirty region logging
- Volume snapshots
- FastResync
- How VxVM handles hardware clones or snapshots
- Volume encryption
- How Veritas File System works
- Section II. Provisioning storage
- Provisioning new storage
- Advanced allocation methods for configuring storage
- Customizing allocation behavior
- Using rules to make volume allocation more efficient
- Understanding persistent attributes
- Customizing disk classes for allocation
- Specifying allocation constraints for vxassist operations with the use clause and the require clause
- Creating volumes of a specific layout
- Customizing allocation behavior
- Creating and mounting VxFS file systems
- Creating a VxFS file system
- Mounting a VxFS file system
- tmplog mount option
- ioerror mount option
- largefiles and nolargefiles mount options
- Resizing a file system
- Monitoring free space
- Extent attributes
- Section III. Administering multi-pathing with DMP
- Administering Dynamic Multi-Pathing
- Discovering and configuring newly added disk devices
- About discovering disks and dynamically adding disk arrays
- How to administer the Device Discovery Layer
- Administering DMP using the vxdmpadm utility
- Gathering and displaying I/O statistics
- Specifying the I/O policy
- Discovering and configuring newly added disk devices
- Dynamic Reconfiguration of devices
- Reconfiguring a LUN online that is under DMP control using the Dynamic Reconfiguration tool
- Manually reconfiguring a LUN online that is under DMP control
- Managing devices
- Displaying disk information
- Changing the disk device naming scheme
- Adding and removing disks
- Event monitoring
- Administering Dynamic Multi-Pathing
- Section IV. Administering Storage Foundation
- Administering sites and remote mirrors
- About sites and remote mirrors
- Fire drill - testing the configuration
- Changing the site name
- Administering the Remote Mirror configuration
- Failure and recovery scenarios
- Administering sites and remote mirrors
- Section V. Optimizing I/O performance
- Veritas File System I/O
- Veritas Volume Manager I/O
- Managing application I/O workloads using maximum IOPS settings
- Section VI. Using Point-in-time copies
- Understanding point-in-time copy methods
- When to use point-in-time copies
- About Storage Foundation point-in-time copy technologies
- Volume-level snapshots
- Storage Checkpoints
- About FileSnaps
- About snapshot file systems
- Administering volume snapshots
- Traditional third-mirror break-off snapshots
- Full-sized instant snapshots
- Creating instant snapshots
- Adding an instant snap DCO and DCO volume
- Controlling instant snapshot synchronization
- Creating instant snapshots
- Cascaded snapshots
- Adding a version 0 DCO and DCO volume
- Administering Storage Checkpoints
- Storage Checkpoint administration
- Administering FileSnaps
- Administering snapshot file systems
- Understanding point-in-time copy methods
- Section VII. Optimizing storage with Storage Foundation
- Understanding storage optimization solutions in Storage Foundation
- Migrating data from thick storage to thin storage
- Maintaining Thin Storage with Thin Reclamation
- Reclamation of storage on thin reclamation arrays
- Identifying thin and thin reclamation LUNs
- Veritas InfoScale 4k sector device support solution
- Section VIII. Maximizing storage utilization
- Understanding storage tiering with SmartTier
- Creating and administering volume sets
- Multi-volume file systems
- Features implemented using multi-volume file system (MVFS) support
- Adding a volume to and removing a volume from a multi-volume file system
- Volume encapsulation
- Load balancing
- Administering SmartTier
- About SmartTier
- Placement classes
- Administering placement policies
- File placement policy rules
- Multiple criteria in file placement policy rule statements
- Using SmartTier with solid state disks
- Sub-file relocation
- Administering hot-relocation
- How hot-relocation works
- Moving relocated subdisks
- Deduplicating data
- Compressing files
- About compressing files
- Use cases for compressing files
- Section IX. Administering storage
- Managing volumes and disk groups
- Rules for determining the default disk group
- Moving volumes or disks
- Monitoring and controlling tasks
- Performing online relayout
- Adding a mirror to a volume
- Managing disk groups
- Disk group versions
- Displaying disk group information
- Importing a disk group
- Moving disk groups between systems
- Importing a disk group containing hardware cloned disks
- Handling conflicting configuration copies
- Destroying a disk group
- Backing up and restoring disk group configuration data
- Managing plexes and subdisks
- Decommissioning storage
- Rootability
- Encapsulating a disk
- Rootability
- Sample supported root disk layouts for encapsulation
- Encapsulating and mirroring the root disk
- Administering an encapsulated boot disk
- Quotas
- Using Veritas File System quotas
- File Change Log
- Managing volumes and disk groups
- Section X. Reference
- Appendix A. Reverse path name lookup
- Appendix B. Tunable parameters
- Tuning the VxFS file system
- Methods to change Dynamic Multi-Pathing tunable parameters
- Tunable parameters for VxVM
- Methods to change Veritas Volume Manager tunable parameters
- Appendix C. Command reference
Restoring from a Storage Checkpoint
Mountable data Storage Checkpoints on a consistent and undamaged file system can be used by backup and restore applications to restore either individual files or an entire file system. Restoration from Storage Checkpoints can also help recover incorrectly modified files, but typically cannot recover from hardware damage or other file system integrity problems.
Note:
For hardware or other integrity problems, Storage Checkpoints must be supplemented by backups from other media.
Files can be restored by copying the entire file from a mounted Storage Checkpoint back to the primary fileset. To restore an entire file system, you can designate a mountable data Storage Checkpoint as the primary fileset using the fsckpt_restore command.
See the fsckpt_restore
(1M) manual page.
When using the fsckpt_restore command to restore a file system from a Storage Checkpoint, all changes made to that file system after that Storage Checkpoint's creation date are permanently lost. The only Storage Checkpoints and data preserved are those that were created at the same time, or before, the selected Storage Checkpoint's creation. The file system cannot be mounted at the time that fsckpt_restore is invoked.
Note:
Individual files can also be restored very efficiently by applications using the fsckpt_fbmap
(3) library function to restore only modified portions of a files data.
You can restore from a Storage Checkpoint only to a file system that has disk layout Version 6 or later.
The following example restores a file, file1.txt
, which resides in your home directory, from the Storage Checkpoint CKPT1
to the device /dev/vx/dsk/dg1/vol-01
. The mount point for the device is /home
.
To restore a file from a Storage Checkpoint
- Create the Storage Checkpoint
CKPT1
of/home
.$ fsckptadm create CKPT1 /home
- Mount Storage Checkpoint
CKPT1
on the directory/home/checkpoints/mar_4
.$ /opt/VRTS/bin/mount -o ckpt=CKPT1 /dev/vx/dsk/dg1/vol- \ 01:CKPT1 /home/checkpoints/mar_4
- Delete the
file1.txt
file from your home directory.$ cd /home/users/me $ rm file1.txt
- Go to the
/home/checkpoints/mar_4/users/me
directory, which contains the image of your home directory.$ cd /home/checkpoints/mar_4/users/me $ ls -l -rw-r--r-- 1 me staff 14910 Mar 4 17:09 file1.txt
- Copy the file
file1.txt
to your home directory.$ cp file1.txt /home/users/me $ cd /home/users/me $ ls -l -rw-r--r-- 1 me staff 14910 Mar 4 18:21 file1.txt
The following example restores a file system from the Storage Checkpoint CKPT3
. The filesets listed before the restoration show an unnamed root fileset and six Storage Checkpoints.
To restore a file system from a Storage Checkpoint
- Run the fsckpt_restore command:
# fsckpt_restore -l /dev/vx/dsk/dg1/vol2 /dev/vx/dsk/dg1/vol2: UNNAMED: ctime = Thu 08 May 2004 06:28:26 PM PST mtime = Thu 08 May 2004 06:28:26 PM PST flags = largefiles, file system root CKPT6: ctime = Thu 08 May 2004 06:28:35 PM PST mtime = Thu 08 May 2004 06:28:35 PM PST flags = largefiles CKPT5: ctime = Thu 08 May 2004 06:28:34 PM PST mtime = Thu 08 May 2004 06:28:34 PM PST flags = largefiles, nomount CKPT4: ctime = Thu 08 May 2004 06:28:33 PM PST mtime = Thu 08 May 2004 06:28:33 PM PST flags = largefiles CKPT3: ctime = Thu 08 May 2004 06:28:36 PM PST mtime = Thu 08 May 2004 06:28:36 PM PST flags = largefiles CKPT2: ctime = Thu 08 May 2004 06:28:30 PM PST mtime = Thu 08 May 2004 06:28:30 PM PST flags = largefiles CKPT1: ctime = Thu 08 May 2004 06:28:29 PM PST mtime = Thu 08 May 2004 06:28:29 PM PST flags = nodata, largefiles
- In this example, select the Storage Checkpoint
CKPT3
as the new root fileset:Select Storage Checkpoint for restore operation or <Control/D> (EOF) to exit or <Return> to list Storage Checkpoints: CKPT3 CKPT3: ctime = Thu 08 May 2004 06:28:31 PM PST mtime = Thu 08 May 2004 06:28:36 PM PST flags = largefiles UX:vxfs fsckpt_restore: WARNING: V-3-24640: Any file system changes or Storage Checkpoints made after Thu 08 May 2004 06:28:31 PM PST will be lost.
- Type y to restore the file system from
CKPT3
:Restore the file system from Storage Checkpoint CKPT3 ? (ynq) y (Yes) UX:vxfs fsckpt_restore: INFO: V-3-23760: File system restored from CKPT3
If the filesets are listed at this point, it shows that the former UNNAMED root fileset and
CKPT6
,CKPT5
, andCKPT4
were removed, and thatCKPT3
is now the primary fileset.CKPT3
is now the fileset that will be mounted by default. - Run the fsckpt_restore command:
# fsckpt_restore -l /dev/vx/dsk/dg1/vol2 /dev/vx/dsk/dg1/vol2: CKPT3: ctime = Thu 08 May 2004 06:28:31 PM PST mtime = Thu 08 May 2004 06:28:36 PM PST flags = largefiles, file system root CKPT2: ctime = Thu 08 May 2004 06:28:30 PM PST mtime = Thu 08 May 2004 06:28:30 PM PST flags = largefiles CKPT1: ctime = Thu 08 May 2004 06:28:29 PM PST mtime = Thu 08 May 2004 06:28:29 PM PST flags = nodata, largefiles Select Storage Checkpoint for restore operation or <Control/D> (EOF) to exit or <Return> to list Storage Checkpoints: