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
Allocation of METADATA Subdisks During Root Disk Encapsulation
METADATA subdisks are created during root disk encapsulation to protect partitioning information. These subdisks are deleted automatically when a root disk is unencapsulated.
The following example fdisk output shows the original partition table for a system's root disk:
# fdisk -ul /dev/hda Disk /dev/hda: 255 heads, 63 sectors, 2431 cylinders Units = sectors of 1 * 512 bytes Device Boot Start End Blocks Id System /dev/hda1 63 2104514 1052226 83 Linux /dev/hda2 2104515 6297479 2096482+ 83 Linux /dev/hda3 6329610 39054014 16362202+ 5 Extended /dev/hda5 6329673 10522574 2096451 83 Linux /dev/hda6 10522638 14715539 2096451 83 Linux /dev/hda7 14715603 18908504 2096451 83 Linux /dev/hda8 18908568 23101469 2096451 83 Linux /dev/hda9 23101533 25205984 1052226 82 Linux swap
Notice that there is a gap between start of the extended partition (hda3) and the start of the first logical partition (hda5). For the logical partitions (hda5 through hda9), there are also gaps between the end of one logical partition and the start of the next logical partition. These gaps contain metadata for partition information. Because these metadata regions lie inside the public region, VxVM allocates subdisks over them to prevent accidental allocation of this space to volumes.
After the root disk has been encapsulated, the output from the vxprint command appears similar to the following:
Disk group: rootdg TY NAME ASSOC KSTATE LENGTH PLOFFS STATE TUTIL0 PUTIL0 dg rootdg rootdg - - - - - - dm disk01 sdh - 17765181 - - - - dm rootdisk hda - 39053952 - - - - sd meta-rootdisk05 - ENABLED 63 - - - METADATA sd meta-rootdisk06 - ENABLED 63 - - - METADATA sd meta-rootdisk07 - ENABLED 63 - - - METADATA sd meta-rootdisk08 - ENABLED 63 - - - METADATA sd meta-rootdisk09 - ENABLED 63 - - - METADATA sd meta-rootdisk10 - ENABLED 63 - - - METADATA sd rootdiskPriv - ENABLED 2049 - - - PRIVATE v bootvol fsgen ENABLED 2104452 - ACTIVE - - pl bootvol-01 bootvol ENABLED 2104452 - ACTIVE - - sd rootdisk-07 bootvol-01 ENABLED 2104452 0 - - - v homevol fsgen ENABLED 4192902 - ACTIVE - - pl homevol-01 homevol ENABLED 4192902 - ACTIVE - - sd rootdisk-05 homevol-01 ENABLED 4192902 0 - - - v optvol fsgen ENABLED 4192902 - ACTIVE - - pl optvol-01 optvol ENABLED 4192902 - ACTIVE - - sd rootdisk-04 optvol-01 ENABLED 4192902 0 - - - v rootvol root ENABLED 4192902 - ACTIVE - - pl rootvol-01 rootvol ENABLED 4192902 - ACTIVE - - sd rootdisk-02 rootvol-01 ENABLED 4192902 0 - - - v swapvol swap ENABLED 2104452 - ACTIVE - - pl swapvol-01 swapvol ENABLED 2104452 - ACTIVE - - sd rootdisk-01 swapvol-01 ENABLED 2104452 0 - - - v usrvol fsgen ENABLED 4192965 - ACTIVE - - pl usrvol-01 usrvol ENABLED 4192965 - ACTIVE - - sd rootdisk-06 usrvol-01 ENABLED 4192965 0 - - - v varvol fsgen ENABLED 4192902 - ACTIVE - - pl varvol-01 varvol ENABLED 4192902 - ACTIVE - - sd rootdisk-03 varvol-01 ENABLED 4192902 0 - - -
The new partition table for the root disk appears similar to the following:
# fdisk -ul /dev/hda Disk /dev/hda: 255 heads, 63 sectors, 2431 cylinders Units = sectors of 1 * 512 bytes Device Boot Start End Blocks Id System /dev/hda1 63 2104514 1052226 83 Linux /dev/hda2 2104515 6297479 2096482+ 83 Linux /dev/hda3 6329610 39054014 16362202+ 5 Extended /dev/hda4 63 39054014 19526976 7e Unknown /dev/hda5 6329673 10522574 2096451 83 Linux /dev/hda6 10522638 14715539 2096451 83 Linux /dev/hda7 14715603 18908504 2096451 83 Linux /dev/hda8 18908568 23101469 2096451 83 Linux /dev/hda9 23101533 25205984 1052226 82 Linux swap /dev/hda10 39051966 39054014 1024+ 7f Unknown
In this example, primary partition hda4 and logical partition hda10 have been created to represent the VxVM public and private regions respectively.