86 IBM Certification Study Guide AIX HACMP
That is, you enter this command for each disk. In the resulting display,
locate the line for the logical volume for which you just added copies. For
copies placed on separate disks, the numbers in the logical partitions
column and the physical partitions column should be equal. Otherwise, the
copies were placed on the same disk and the mirrored copies will not
protect against disk failure.
Testing a File System
To run a consistency check on each file system’s information:
1. Enter:
fsck /filesystem_name
2. Verify that you can mount the file system by entering:
mount /filesystem_name
3. Verify that you can unmount the file system by entering:
umount /filesystem_name
3.4.3 Mirroring Strategies
Shared logical volumes residing on non-RAID disk devices should be
mirrored in AIX to eliminate the disk as a single point of failure. Shared
volume groups residing on a RAID device should not be AIX mirrored; the
disk array provides its own data redundancy.
The copies should reside on separate disks that are controlled by different
disk adapters and are located in separate drawers or units, if possible.
3.4.4 Importing to Other Nodes
The following sections cover: varying off a volume group on the source node,
importing it onto the destination node, changing its startup status, and varying
it off on the destination nodes.
3.4.4.1 Varying Off a Volume Group on the Source Node
After completing the previous tasks, use the
varyoffvg command to
deactivate the shared volume group. You vary off the volume group so that it
can be properly imported onto a destination node and activated as
appropriate by the cluster event scripts. Enter the following command:
varyoffvg volume_group_name. Make sure that all the file systems of the
volume group have been unmounted, otherwise the
varyoffvg command will
not work.
3.4.4.2 Importing a Volume Group onto the Destination Node
This section covers how to import a volume group onto destination nodes
using the SMIT interface. You can also use the TaskGuide utility for this task.
