3.5.1 Matrix Server Administration Guide

Chapter 7: Configure PSFS Filesystems 94

to take the appropriate actions. For example, if you want to spread a

kernel build across four servers, you will need to run a cooperative make.

Journaling Filesystem

When you initiate certain filesystem operations such as creating, opening,

or moving a file or modifying its size, the filesystem writes the metadata,

or structural information, for that event to a transaction journal. The

filesystem then performs the operation.

If a server using the filesystem should crash during an operation, the

journal is replayed and any journaled operations in progress at the time

of the crash are completed. This procedure ensures that the structure of

the filesystem is consistent. Users on other servers will experience only a

slight delay in filesystem operations during the recovery.

Server Registry

Matrix Server uses a registry to control server access to PSFS filesystems

on the SAN disks imported into the matrix. A server is added to the

registry when it mounts its first PSFS filesystem. Under normal

operations, a server remains in the registry until it either unmounts its

last PSFS filesystem or leaves the matrix.

However, if a server crashes or loses communication with the matrix and

that server is in the registry (indicating that it had active PSFS mounts),

Matrix Server will remove the server’s access to the filesystems. When

this situation occurs, an alert will appear on the Management Console

and a message will be written to the matrix log. You will need to reboot

the server to restore its access.

After the server is rebooted and rejoins the matrix, it is deleted from the

registry. When the server again mounts a PSFS filesystem, it will be

added back into the registry.