Storage Foundation Cluster File System High Availability 7.2 Administrator's Guide - Solaris
- Section I. Introducing Storage Foundation Cluster File System High Availability
- Overview of Storage Foundation Cluster File System High Availability
- About Veritas File System
- About Storage Foundation Cluster File System (SFCFS)
- How Dynamic Multi-Pathing works
- How DMP 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
- How Veritas File System works
- How Storage Foundation Cluster File System High Availability works
- About Storage Foundation Cluster File System High Availability architecture
- About Veritas File System features supported in cluster file systems
- About single network link and reliability
- About I/O fencing
- About preventing data corruption with I/O fencing
- About I/O fencing components
- About server-based I/O fencing
- About secure communication between the SFCFSHA cluster and CP server
- How Cluster Volume Manager works
- Overview of clustering
- Cluster Volume Manager (CVM) tolerance to storage connectivity failures
- Storage disconnectivity and CVM disk detach policies
- CVM initialization and configuration
- Dirty region logging in cluster environments
- Multiple host failover configurations
- About Flexible Storage Sharing
- Overview of Storage Foundation Cluster File System High Availability
- 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
- Managing DMP devices for the ZFS root pool
- 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 Cluster File System High Availability
- Administering Storage Foundation Cluster File System High Availability and its components
- Administering CFS
- About the mount, fsclustadm, and fsadm commands
- When the CFS primary node fails
- About Snapshots on SFCFSHA
- Administering VCS
- Administering CVM
- About setting cluster node preferences for master failover
- About changing the CVM master manually
- Importing disk groups as shared
- Administering Flexible Storage Sharing
- Administering ODM
- About administering I/O fencing
- About the vxfentsthdw utility
- Testing the coordinator disk group using the -c option of vxfentsthdw
- About the vxfenadm utility
- About the vxfenclearpre utility
- About the vxfenswap utility
- About administering the coordination point server
- About migrating between disk-based and server-based fencing configurations
- Migrating between fencing configurations using response files
- About the vxfentsthdw utility
- Administering SFCFSHA global clusters
- Using Clustered NFS
- Understanding how Clustered NFS works
- Configure and unconfigure Clustered NFS
- Reconciling major and minor numbers for NFS shared disks
- Administering Clustered NFS
- Samples for configuring a Clustered NFS
- Using Common Internet File System
- Deploying Oracle with Clustered NFS
- 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 Storage Foundation Cluster File System High Availability and its components
- Section V. Optimizing I/O performance
- Section VI. Veritas Extension for Oracle Disk Manager
- Using Veritas Extension for Oracle Disk Manager
- About Oracle Disk Manager
- About Oracle Disk Manager and Oracle Managed Files
- Using Cached ODM
- Using Veritas Extension for Oracle Disk Manager
- Section VII. 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 VIII. Optimizing storage with Storage Foundation Cluster File System High Availability
- Understanding storage optimization solutions in Storage Foundation Cluster File System High Availability
- 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 IX. 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 on Solaris SPARC
- Compressing files
- About compressing files
- Use cases for compressing files
- Section X. 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
- Administering an encapsulated boot disk
- Quotas
- Using Veritas File System quotas
- File Change Log
- Managing volumes and disk groups
- Section XI. 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
- About LLT tunable parameters
- About GAB tunable parameters
- About VXFEN tunable parameters
- Appendix C. Veritas File System disk layout
- Appendix D. Command reference
- Appendix E. Creating a starter database
How hot-relocation works
Hot-relocation allows a system to react automatically to I/O failures on redundant (mirrored or RAID-5) VxVM objects, and to restore redundancy and access to those objects. VxVM detects I/O failures on objects and relocates the affected subdisks to disks designated as spare disks or to free space within the disk group. VxVM then reconstructs the objects that existed before the failure and makes them redundant and accessible again.
When a partial disk failure occurs (that is, a failure affecting only some subdisks on a disk), redundant data on the failed portion of the disk is relocated. Existing volumes on the unaffected portions of the disk remain accessible.
Hot-relocation is only performed for redundant (mirrored or RAID-5) subdisks on a failed disk. Non-redundant subdisks on a failed disk are not relocated, but the system administrator is notified of their failure.
Hot-relocation is enabled by default and takes effect without the intervention of the system administrator when a failure occurs.
The hot-relocation daemon, vxrelocd, detects and reacts to VxVM events that signify the following types of failures:
This is normally detected as a result of an I/O failure from a VxVM object. VxVM attempts to correct the error. If the error cannot be corrected, VxVM tries to access configuration information in the private region of the disk. If it cannot access the private region, it considers the disk failed. | |
This is normally detected as a result of an uncorrectable I/O error in the plex (which affects subdisks within the plex). For mirrored volumes, the plex is detached. | |
This is normally detected as a result of an uncorrectable I/O error. The subdisk is detached. |
When vxrelocd detects such a failure, it performs the following steps:
vxrelocd informs the system administrator (and other nominated users) by electronic mail of the failure and which VxVM objects are affected.
See Partial disk failure mail messages.
vxrelocd next determines if any subdisks can be relocated. vxrelocd looks for suitable space on disks that have been reserved as hot-relocation spares (marked spare) in the disk group where the failure occurred. It then relocates the subdisks to use this space.
If no spare disks are available or additional space is needed, vxrelocd uses free space on disks in the same disk group, except those disks that have been excluded for hot-relocation use (marked nohotuse). When vxrelocd has relocated the subdisks, it reattaches each relocated subdisk to its plex.
Finally, vxrelocd initiates appropriate recovery procedures. For example, recovery includes mirror resynchronization for mirrored volumes or data recovery for RAID-5 volumes. It also notifies the system administrator of the hot-relocation and recovery actions that have been taken.
If relocation is not possible, vxrelocd notifies the system administrator and takes no further action.
Warning:
Hot-relocation does not guarantee the same layout of data or the same performance after relocation. An administrator should check whether any configuration changes are required after hot-relocation occurs.
Relocation of failing subdisks is not possible in the following cases:
The failing subdisks are on non-redundant volumes (that is, volumes of types other than mirrored or RAID-5).
There are insufficient spare disks or free disk space in the disk group.
The only available space is on a disk that already contains a mirror of the failing plex.
The only available space is on a disk that already contains the RAID-5 log plex or one of its healthy subdisks. Failing subdisks in the RAID-5 plex cannot be relocated.
If a mirrored volume has a dirty region logging (DRL) log subdisk as part of its data plex, failing subdisks belonging to that plex cannot be relocated.
If a RAID-5 volume log plex or a mirrored volume DRL log plex fails, a new log plex is created elsewhere. There is no need to relocate the failed subdisks of the log plex.
See the vxrelocd(1M) manual page.
Figure: Example of hot-relocation for a subdisk in a RAID-5 volume shows the hot-relocation process in the case of the failure of a single subdisk of a RAID-5 volume.