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
Using vxassist
You can use the vxassist utility to create and modify volumes. Specify the basic requirements for volume creation or modification, and vxassist performs the necessary tasks.
The advantages of using vxassist rather than the advanced approach include:
Most actions require that you enter only one command rather than several.
You are required to specify only minimal information to vxassist. If necessary, you can specify additional parameters to modify or control its actions.
Operations result in a set of configuration changes that either succeed or fail as a group, rather than individually. System crashes or other interruptions do not leave intermediate states that you have to clean up. If vxassist finds an error or an exceptional condition, it exits after leaving the system in the same state as it was prior to the attempted operation.
The vxassist utility helps you perform the following tasks:
Creating volumes.
Creating mirrors for existing volumes.
Growing or shrinking existing volumes.
Backing up volumes online.
Reconfiguring a volume's layout online.
vxassist obtains most of the information it needs from sources other than your input. vxassist obtains information about the existing objects and their layouts from the objects themselves.
For tasks requiring new disk space, vxassist seeks out available disk space and allocates it in the configuration that conforms to the layout specifications and that offers the best use of free space.
The vxassist command takes this form:
# vxassist [options] keyword volume [attributes...]
where keyword selects the task to perform. The first argument after a vxassist keyword, volume, is a volume name, which is followed by a set of desired volume attributes. For example, the keyword make allows you to create a new volume:
# vxassist [options] make volume length [attributes]
The length of the volume can be specified in sectors, kilobytes, megabytes, or gigabytes by using a suffix character of s, k, m, or g. If no suffix is specified, the size is assumed to be in sectors.
See the vxintro(1M) manual page.
Additional attributes can be specified as appropriate, depending on the characteristics that you wish the volume to have. Examples are stripe unit width, number of columns in a RAID-5 or stripe volume, number of mirrors, number of logs, and log type.
By default, the vxassist command creates volumes in a default disk group according to a set of rules.
To use a different disk group, specify the -g diskgroup option to vxassist.
A large number of vxassist keywords and attributes are available for use.
See the vxassist(1M) manual page.
The simplest way to create a volume is to use default attributes.
More complex volumes can be created with specific attributes by controlling how vxassist uses the available storage space.