Veritas™ Volume Manager Administrator's Guide
- Understanding Veritas Volume Manager
- VxVM and the operating system
- How VxVM handles storage management
- Volume layouts in VxVM
- Online relayout
- Volume resynchronization
- Dirty region logging
- Volume snapshots
- FastResync
- Provisioning new usable storage
- Administering disks
- Disk devices
- Discovering and configuring newly added disk devices
- Discovering disks and dynamically adding disk arrays
- How to administer the Device Discovery Layer
- Changing the disk-naming scheme
- Adding a disk to VxVM
- Rootability
- Displaying disk information
- Removing disks
- Removing and replacing disks
- Administering Dynamic Multi-Pathing
- How DMP works
- Administering DMP using vxdmpadm
- Gathering and displaying I/O statistics
- Specifying the I/O policy
- Online dynamic reconfiguration
- Reconfiguring a LUN online that is under DMP control
- Creating and administering disk groups
- About disk groups
- Displaying disk group information
- Creating a disk group
- Importing a disk group
- Moving disk groups between systems
- Handling cloned disks with duplicated identifiers
- Handling conflicting configuration copies
- Reorganizing the contents of disk groups
- Destroying a disk group
- Creating and administering subdisks and plexes
- Displaying plex information
- Reattaching plexes
- Creating volumes
- Types of volume layouts
- Creating a volume
- Using vxassist
- Creating a volume on specific disks
- Creating a mirrored volume
- Creating a striped volume
- Creating a volume using vxmake
- Initializing and starting a volume
- Using rules and persistent attributes to make volume allocation more efficient
- Administering volumes
- Displaying volume information
- Monitoring and controlling tasks
- Reclamation of storage on thin reclamation arrays
- Stopping a volume
- Resizing a volume
- Adding a mirror to a volume
- Preparing a volume for DRL and instant snapshots
- Adding traditional DRL logging to a mirrored volume
- Enabling FastResync on a volume
- Performing online relayout
- Adding a RAID-5 log
- Creating and administering volume sets
- Configuring off-host processing
- Administering hot-relocation
- How hot-relocation works
- Moving relocated subdisks
- Administering cluster functionality (CVM)
- Overview of clustering
- Multiple host failover configurations
- CVM initialization and configuration
- Dirty region logging in cluster environments
- Administering VxVM in cluster environments
- Changing the CVM master manually
- Importing disk groups as shared
- 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
- Performance monitoring and tuning
- Appendix A. Using Veritas Volume Manager commands
- Appendix B. Configuring Veritas Volume Manager
Creating a volume on specific disks
VxVM automatically selects the disks on which each volume resides, unless you specify otherwise. If you want a volume to be created on specific disks, you must designate those disks to VxVM. More than one disk can be specified.
To create a volume on a specific disk or disks, use the following command:
# vxassist [-b] [-g diskgroup] make volume length \ [layout=layout] diskname ...
Specify the -b option if you want to make the volume immediately available for use.
For example, to create the volume volspec with length 5 gigabytes on disks mydg03 and mydg04, use the following command:
# vxassist -b -g mydg make volspec 5g mydg03 mydg04
The vxassist command allows you to specify storage attributes. These give you control over the devices, including disks, controllers and targets, which vxassist uses to configure a volume. For example, you can specifically exclude disk mydg05.
Note:
The ! character is a special character in some shells. The following examples show how to escape it in a bash shell.
# vxassist -b -g mydg make volspec 5g \!mydg05
The following example excludes all disks that are on controller c2:
# vxassist -b -g mydg make volspec 5g \!ctlr:c2
This example includes only disks on controller c1 except for target t5:
# vxassist -b -g mydg make volspec 5g ctlr:c1 \!target:c1t5
If you want a volume to be created using only disks from a specific disk group, use the -g option to vxassist, for example:
# vxassist -g bigone -b make volmega 20g bigone10 bigone11
or alternatively, use the diskgroup attribute:
# vxassist -b make volmega 20g diskgroup=bigone bigone10 \ bigone11
Any storage attributes that you specify for use must belong to the disk group. Otherwise, vxassist will not use them to create a volume.
You can also use storage attributes to control how vxassist uses available storage, for example, when calculating the maximum size of a volume, when growing a volume or when removing mirrors or logs from a volume. The following example excludes disks dgrp07 and dgrp08 when calculating the maximum size of RAID-5 volume that vxassist can create using the disks in the disk group dg:
# vxassist -b -g dgrp maxsize layout=raid5 nlog=2 \!dgrp07 \!dgrp08
It is also possible to control how volumes are laid out on the specified storage.
See the vxassist(1M) manual page.
vxassist also lets you select disks based on disk tags. The following command only includes disks that have a tier1 disktag.
# vxassist -g dg3 make vol3 1g disktag:tier1