VERITAS Volume Manager 3.1 Administrator's Guide

Volume Manager Operations

Dynamic Multipathing (DMP)

Chapter 3124

Step 5. Run the following script

# /etc/vx/bin/vxdmpdis

If all the above steps complete successfully, reboot the system. When the

system comes up, DMP should be removed completely from the system.

Verify that DMP was removed by running the vxdmpadm command. The

following message is displayed:

vxvm:vxdmpadm: ERROR: vxdmp module is not loaded on the

system. Command invalid.

Also the command vxdisk list <da_name> should not display any

multipathing information.

Enabling DMP on a HP System (Where it is Currently Disabled): Step 1.Stop the

vxconfigd daemon using the following command:

# vxdctl stop

Step 2. Save the /stand/system ﬁle as /stand/system.vxdmpdis by

executing the command:

# cp /stand/system /stand/system.vxdmpdis

Step 3. Save the /stand/vmunix ﬁle as /stand/vmunix.vxdmpdis by

executing the command:

# cp /stand/vmunix /stand/vmunix.vxdmpdis

Step 4. Edit the /stand/system ﬁle and add the vxdmp entry to it (after the

vxvm entry).

Step 5. Run the following script:

# /etc/vx/bin/vxdmpen

After the above steps complete successfully, reboot the system. When the

system comes up, DMP should be enabled on the system. Verify this by

running the vxdmpadm command. This command shows multipathing

information. Also, the command vxdisk list <da_name> shows

multipathing information.

Input/Output (I/O) Controllers

This feature allows the administrator to turn off I/Os to a host I/O

controller to perform administrative operations. It can be used for