3.1.2 Matrix Server Administration Guide

Chapter 18: SAN Maintenance 239

3. Clear the host registry on the matrix. On one server, issue the

command mxmpconf at the operating system prompt. Then select

“Repair” from the Main Menu. On the Repair Menu, select the option

to clear the host registry.

4. Run mxconfig from one server in the matrix. Skip the opening

windows and then configure the appropriate fencing method.

5. When you have completed the fencing configuration, skip the

membership partition configuration windows and then export the

new configuration to the other servers in the matrix.

6. Start Matrix Server on each server:

# /etc/init.d/pmxs start

7. Verify the fencing configuration as described in the PolyServe Matrix

Server Installation Guide.

Changing the Number of LUNs Can Cause

Matrix Failure

Matrix Server uses worldwide names and LUN numbers to associate PSD

device names with SAN devices. If the LUN numbers are changed on an

array (for example, by combining LUNs or breaking a LUN into multiple

LUNs), the matrix can fail to start when servers are rebooted because the

PSD device names are no longer associated with the correct LUNs. Matrix

Server cannot automatically detect a change in LUN numbering because

its identification mechanism uses the worldwide name, which changes as

the LUN changes.

To minimize downtime, if you need to make changes to your storage

which will result in the LUN numbers on the array changing, contact

PolyServe Technical Support before making the change.

However, if this situation should occur, you can use the mxmpconf utility

to restore the membership partitions. You will then be able to restart the

matrix. For assistance in restoring access to PSFS filesystems, contact

PolyServe Technical Support.

NOTE: LUNs can safely be resized. Problems occur only if LUN

numbering on the array is changed.