Using rules and persistent attributes to make volume allocation more efficient

The vxassist command lets you create a set of volume allocation rules and define it with a single name. When you specify this name in your volume allocation request, all the attributes that are defined in this rule are honored when vxassist creates the volume.

When you create rules, you do not define them in the /etc/default/vxassist file. You create the rules in another file and add the path information to /etc/default/vxassist. By default, a rule file is loaded from /etc/default/vxsf_rules. You can override this location in /etc/default/vxassist with the attribute rulefile=/path/rule_file_name. You can also specify additional rule files on the command line.

Creating volume allocation rules has the following benefits:

For example, you can create allocation rules so that a set of servers can standardize their storage tiering. Suppose you had the following requirements:

Tier 1

Enclosure mirroring between a specific set of array types

Tier 2

Non-mirrored striping between a specific set of array types

Tier 0

Select solid-state drive (SSD) storage

You can create rules for each volume allocation requirement and name the rules tier1, tier2, and tier0.

You can also define rules so that each time you create a volume for a particular purpose, it's created with the same attributes. For example, to create the volume for a production database, you can create a rule called productiondb. To create standardized volumes for home directories, you can create a rule called homedir. To standardize your high performance index volumes, you can create a rule called dbindex.