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
Automatic site reattachment
The automatic site reattachment daemon, vxattachd, provides automatic reattachment of sites. The vxattachd daemon uses the vxnotify mechanism to monitor storage coming back online on a site after a previous failure, and to restore redundancy of mirrors across sites.
If the hot-relocation daemon, vxrelocd, is running, vxattachd attempts to reattach the site, and allows vxrelocd to try to use the available disks in the disk group to relocate the failed subdisks. If vxrelocd succeeds in relocating the failed subdisks, it starts the recovery of the plexes at the site. When all the plexes have been recovered, the plexes are put into the ACTIVE state, and the state of the site is set to ACTIVE.
If vxrelocd is not running, vxattachd reattaches a site only when all the disks at that site become accessible. After reattachment succeeds, vxattachd sets the site state to ACTIVE, and initiates recovery of the plexes. When all the plexes have been recovered, the plexes are put into the ACTIVE state.
Note:
vxattachd does not try to reattach a site that you have explicitly detached by using the vxdg detachsite command.
The automatic site reattachment feature is enabled by default. The vxattachd daemon uses email to notify root of any attempts to reattach sites and to initiate recovery of plexes at those sites.
To send mail to other users, add the user name to the line that starts vxattachd in the /sbin/init.d/vxvm-recover
startup script, and reboot the system.
If you do not want a site to be recovered automatically, kill the vxattachd daemon, and prevent it from restarting. If you stop vxattachd, the automatic plex reattachment also stops. To kill the daemon, run the following command from the command line:
# ps -afe
Locate the process table entry for vxattachd, and kill it by specifying its process ID:
# kill -9 PID
If there is no entry in the process table for vxattachd, the automatic site reattachment feature is disabled.
To prevent the automatic site reattachment feature from being restarted, comment out the line that starts vxattachd in the /sbin/init.d/vxvm-recover
startup script.