InfoScale™ 9.0 Solutions Guide - Linux
- Section I. Introducing Veritas InfoScale
- Section II. Solutions for Veritas InfoScale products
- Solutions for Veritas InfoScale products
- Solutions for Veritas InfoScale products
- Section III. Stack-level migration to IPv6 or dual stack
- Section IV. Improving database performance
- Overview of database accelerators
- Improving database performance with Veritas Concurrent I/O
- Improving database performance with atomic write I/O
- Section V. Using point-in-time copies
- Understanding point-in-time copy methods
- Backing up and recovering
- Preserving multiple point-in-time copies
- Online database backups
- Backing up on an off-host cluster file system
- Database recovery using Storage Checkpoints
- Backing up and recovering in a NetBackup environment
- Off-host processing
- Creating and refreshing test environments
- Creating point-in-time copies of files
- Section VI. Maximizing storage utilization
- Optimizing storage tiering with SmartTier
- Optimizing storage with Flexible Storage Sharing
- Optimizing storage tiering with SmartTier
- Section VII. Migrating data
- Understanding data migration
- Offline migration from LVM to VxVM
- Offline conversion of native file system to VxFS
- Online migration of a native file system to the VxFS file system
- Migrating a source file system to the VxFS file system over NFS v4
- VxFS features not available during online migration
- Migrating storage arrays
- Migrating data between platforms
- Overview of the Cross-Platform Data Sharing (CDS) feature
- CDS disk format and disk groups
- Setting up your system to use Cross-platform Data Sharing (CDS)
- Maintaining your system
- Disk tasks
- Disk group tasks
- Displaying information
- File system considerations
- Specifying the migration target
- Using the fscdsadm command
- Maintaining the list of target operating systems
- Migrating a file system on an ongoing basis
- Converting the byte order of a file system
- Migrating from Oracle ASM to Veritas File System
- Section VIII. Veritas InfoScale 4K sector device support solution
- Section IX. REST API support
- Support for configurations and operations using REST APIs
- Support for configurations and operations using REST APIs
- Section X. Reference
Restoring CDS disk labels
CDS disks have the following labels:
Platform block
AIX coexistence label
HP-UX coexistence or VxVM ID block
There are also backup copies of each. If any of the primary labels become corrupted, VxVM will not bring the disk online and user intervention is required.
If two labels are intact, the disk is still recognized as a cdsdisk (though in the error state) and vxdisk flush can be used to restore the CDS disk labels from their backup copies.
Note:
For disks larger than 1 TB, cdsdisks use the EFI layout. The procedure to restore disk labels does not apply to cdsdisks with EFI layout.
Note:
The platform block is no longer written in the backup label. vxdisk flush cannot be used to restore the CDS disk label from backup copies.
Primary labels are at sectors 0, 7, and 16; and a normal flush will not flush sectors 7 and 16. Also, the private area is not updated as the disk is not in a disk group. There is no means of finding a "good" private region to flush from. In this case, it is possible to restore the CDS disk labels from the existing backups on disk using the flush operation.
If a corruption happened after the labels were read and the disk is still online and part of a disk group, then a flush operation will also flush the private region.
Warning:
Caution and knowledge must be employed because the damage could involve more than the CDS disk labels. If the damage is constrained to the first 128K, the disk flush would fix it. This could happen if another system on the fabric wrote a disk label to a disk that was actually a CDS disk in some disk group.
To rewrite the CDS ID information on a specific disk
Type the following command:
# vxdisk flush disk_access_name
This rewrites all labels except sectors 7 and 16.
To rewrite all the disks in a CDS disk group
Type the following command:
# vxdg flush diskgroup
This rewrites all labels except sectors 7 and 16.
To forcibly rewrite the AIX coexistence label in sector 7 and the HP-UX coexistence label or VxVM ID block in sector 16
Type the following command:
# vxdisk -f flush disk_access_name
This command rewrites all labels if there exists a valid VxVM ID block that points to a valid private region. The -f option is required to rewrite sectors 7 and 16 when a disk is taken offline due to label corruption (possibly by a Windows system on the same fabric).