HP Veritas Volume Manager 5.0 -UX 11i v3 Disk groups, Checking “on disk config” size (vxse_dg3), Checking the version number of disk groups (vxse_dg4), See, on page, See “Adding a RAID-5log” on page

Using Storage Expert 451

Identifying configuration problems using Storage Expert

A mirror of the RAID-5 log protects against loss of data due to the failure of a single disk. You are strongly advised to mirror the log if vxse_raid5log3 reports that the log of a large RAID-5 volume does not have a mirror.

See “Adding a RAID-5 log” on page 283.

Disk groups

Disks groups are the basis of VxVM storage configuration so it is critical that the integrity and resilience of your disk groups are maintained. Storage Expert provides a number of rules that enable you to check the status of disk groups and associated objects.

Checking whether a configuration database is too full (vxse_dg1)

To check whether the disk group configuration database has become too full, run rule vxse_dg1.

By default, this rule suggests a limit of 250 for the number of disks in a disk group. If one of your disk groups exceeds this figure, you should consider creating a new disk group. The number of objects that can be configured in a disk group is limited by the size of the private region which stores configuration information about every object in the disk group. Each disk in the disk group that has a private region stores a separate copy of this configuration database.

See “Creating a disk group” on page 170.Checking disk group configuration copies and logs (vxse_dg2)

To check whether a disk group has too many or too few disk group configuration copies, and whether a disk group has too many or too few copies of the disk group log, run rule vxse_dg2.

Checking “on disk config” size (vxse_dg3)

To check whether a disk group has the correct “on disk config” size, run rule vxse_dg3.

Checking the version number of disk groups (vxse_dg4)To check the version number of a disk group, run rule vxse_dg4.

For optimum results, your disk groups should have the latest version number that is supported by the installed version of VxVM.

See “Upgrading a disk group” on page 208.