JournaledFileSystemSettings stanza

Settings under this stanza apply to each specified journaled file system unless they are overridden for individual file systems in an override stanza.

File systems that you specify in the JournalFileSystems.Extended stanza override any file systems specified in the list of journaled file systems that you might have previously specified in the JournaledFileSystemSettings stanza. Any other options that you have specified in the JournaledFileSystemsSettings stanza are preserved.

The syntax for the JournaledFileSystemSettings stanza is as follows:

Syntax for JournaledFileSystemSettings stanza:: [JournaledFileSystemSettings]
Syntax for stanza settings:: JournaledFileSystemSetting=value

You can specify the following JournaledFileSystemSettings values:

JournaledFileSystems

Specifies a space delimited list of file systems to journal. Full file system specifications and Windows junctions are supported. There is no default value. You must specify at least one journaled file system for the journal daemon to run. Journaled file systems can be added or removed online without having to restart the daemon. For example:

  JournaledFileSystems=/home /other

Important: The journal selects object names based strictly on a string match. The implication for the user is that care must be taken when selecting file systems to journal. For example, suppose you have a file system /jbb and another file system called /jbb/mnt1. If you ask the journal to monitor just /jbb, then all the changes for /jbb/mnt1 also match this string and are entered in the database. When, however, you do a back up on the client, it parses the name based on file systems, realizes the journal is not monitoring this file system and then tells the journal to remove the /jbb/mnt1 files from the database. The solution is to either monitor both or use the JournalExcludeList. The same is true for the virtual mount point options. You must be consistent with this list. For example, if you specify /home/student1 as a virtual mount point in your dsm.sys option file and you want to journal /home, then you must specify

JournaledFileSystems=/home
/home/student1

. In this case, two separate databases are created.

JournalDbSize

Specifies the maximum size the journal database can grow. The journal database size is expressed in bytes. A value of zero (0) indicates that the database size is limited only by the capacity of the file system containing the journal database. The default is 0 (unlimited). For example:

  JournalDBSize=0x10000000

NotifyBufferSize, DirNotifyBufferSize

Specify change notification buffer sizes for a journaled file system. A large amount of change activity on a journaled file system might require this to be increased. The default is 0x00020000 (128 k) for files and 0x00010000 ( 64 k) for directories.

  NotifyBufferSize=0x00200000

PreserveDbOnExit setting

This setting allows a journal to remain valid when a journaled file system goes offline and comes back online. This is useful for preserving the journal during system reboots, and resource movement.

This setting allows a journal-based backup to continue processing when the daemon is restarted (or the file system comes back online) without performing a full incremental backup.

Note: Any change activity which occurs while the journal daemon is not running (or the file system is offline) is not recorded in the journal.

A value of 1 specifies that the journaled file system journal database is not deleted when the journal file system goes offline. The database is also valid when the journal file system comes back online. This value should be used with caution because any file system change activity which occurs while the journaled file system is offline is not reflected in the journal database. The default setting of 0 deletes the journaled file system journal database.

Note: The journal is only preserved when a journaled file system comes offline normally or is brought offline when the resource is no longer available and you specify the deferFsMonStart setting. If a file system comes offline due to an error such as a notification buffer overrun, the journal is not preserved.

Note: Set PreserveDBonExit only when you can ensure that there is a controlled shutdown of the journal service. The scope of "controlled shutdown" includes stopping the journal service in order to reboot the system, failing over a cluster resource, or moving a cluster resource. The journal database can become corrupted if the shutdown is not controlled. Therefore, perform the following steps if the journal service was not shut down in a controlled manner or if the journal database was otherwise taken offline in an uncontrolled manner.

Stop the journal service (if it is running)
Delete the corrupted journal databases
Restart the journal service
Perform an incremental backup

An example for not deleting the journal database upon exit is:

preserveDBOnExit=1

deferFSMonStart setting

This setting defers an attempt to begin monitoring a file system in the following cases:

When the specified journaled file system is not valid or available
The journal directory for the specified journaled file system cannot be accessed or created

Resources are checked at the interval you specify using the deferRetryInterval setting.

A value of 1 indicates that the setting is on. A value of 0 indicates that the setting is off. The default value is off (set to 0) .

deferRetryInterval setting

This setting specifies the value in seconds that deferred file systems with the deferRetryInterval setting enabled are checked for availability and brought online. The default value is 5 seconds.

logFSErrors setting

A value of 1 indicates that all errors encountered accessing a journaled file system or journal directory should be logged. A value of zero indicates that logging of errors encountered while checking deferred file systems and journal directories is suppressed. This is usually used in conjunction with the deferFSMonStart setting to eliminate excessive File System Unavailable messages from being written to the logs when bringing a journaled file system online is deferred. The default value is 1 (log all errors).