12.2.2 Setting up a LUN-based backup To back up the system using the LUN-based backup method, all the LUNs in the System Pool and User Pools must be in a static, consistent state, to ensure a static state of the SAN File System LUNs both for the metadata and the user data. The following steps are used: 1. Stop or pause all SAN File System client applications. Since this task is application-specific, you will need to follow the application documentation for details on performing this step. 2. Quiesce the SAN File System MDS using the quiescecluster command on the master MDS (see Example 12-1). This ensures that the SAN File System MDS and all clients have completed all active transactions, and flushes their data to disk. Example 12-1 quiescecluster command sfscli> quiescecluster -state full CMMNP5229I Cluster successfully in quiescent state. This procedure will also lock out any subsequent new I/O from the clients or MDS. 3. Copy the following critical system configuration files from each of the MDSs to offline media, such as tape or another system, for example, the Master Console. These files will be different on each MDS, so ensure that you copy them for each MDS separately. Example 12-2 shows part of the copy operation for our LAB setup. You will have to use a secure copy (scp) or secure ftp (sftp) utility, such as provided those by Cygwin or PuTTY. The files are: ­ /etc/init.d/boot.local ­ /etc/sysconfig/network/routes ­ /etc/sysconfig/network/ifcfg-eth0