VERITAS Storage Foundation 4.1 Cross-Platform Data Sharing Administrator's Guide

Chapter 3, Maintaining Your System

Disk Group Tasks

If you need to change the size after creating, you need to remove and rebuild the logs, using the

following commands:

# vxassist -g diskgroup remove log volume nlog=0

# vxassist -g diskgroup addlog volume nlog=nlogs logtype=drl \

logmap_len=len-bytes [drlloglen=len]

Note the following restrictions:

◆ If only logmap_len is specified, the DRL log size is set to the default value (33*DG

alignment).

◆ If logmap_len is greater than (DRL log size)/2, the command fails, and you need to

either provide a sufficiently large loglen value or reduce logmap_len.

◆ For CDS disk groups, the DRL map and log sizes are set to a minimum of 2*(DG alignment).

Creating a DRL Log

You can create a DRL log using one of the following commands:

◆ vxassist

◆ vxvol

Using vxassist to Create a DRL Log

When using the vxassist command to create a DRL log, it creates logging subdisks equal to the

size of the DRL log.

# vxassist -g dgTestSol2 make drlvol 100m mirror=2 logtype=drl \

loglen=264k logmap_len=2048

If neither logmap_len nor loglen is specified, then:

◆ loglen is set to a default value based on disk group alignment.

◆ maplen is set to a reasonable value.

If only loglen is specified, then:

◆ For pre-version 110 disk groups, maplen is set to zero.

◆ For version 110 and greater disk groups, maplen set to use all the bytes available in on-disk

map.

If only logmap_len is specified (this applies only to disk groups with a version of 110 or

greater), maplen must be less than number of available bytes in on-disk map for the default log

length.