This document describes the standards for assigning AIX Volume Group (VG) names. A single standard has been developed for use in standalone, High Availability, and Disaster Recovery environments. This VG naming standard provides the mechanism to assign enterprise wide unique names to all AIX VG's and will eliminate naming conflicts in the event of a manual or automated failover, or if multiple instances of an application are running on a single server.
To assign enterprise wide unique VG names, the system administrator must first define the resource groups names. Once the resource group names have been defined, then a VG name may be defined based on the resource group name.
A single system may contain multiple resource groups, and typically there will be one VG defined per resource group. However, a resource group may contain several VG's, depending upon the requirements of the application.
To define a VG name, obtain the 8 character resource group name, then add a 2 digit volume group sequence number that will uniquely identify the VG, followed by the characters "vg". The VG name will always end with the characters "vg".
The VG name shall consist of exactly 12 characters with the following structure:
ApplicationCode + Environment + Function + Company + Sequence ID + VG Sequence ID + "vg"
3 char + 1 char + 1 char + 2 char + 1 char + 2 char + 2 char
As an example, a resource group named "egaapmx0", may have multiple associated VG's:
|
RG Name Component |
VG Sequence Identifier |
LV Identifier | VG Name |
|---|---|---|---|
| egaapmx0 | 00 | vg | egaapmx000vg |
| egaapmx0 | 01 | vg | egaapmx001vg |
| egaapmx0 | 02 | vg | egaapmx002vg |
Each VG also requires a system or cluster wide unique Major Number. A unique major number can be generated using the following algorithm:
MajorNbr=$( print "${VGNAME}" | sum -o | awk '{ print $1 }' )
To reiterate, before creating a VG, first establish an enterprise wide unique resource group name, a VG name, and a major number. Then create the VG.