File System Logging

Logging is required for cluster file systems. Sun Cluster supports the following logging file systems.

• Solaris UFS logging

• Solstice DiskSuite trans-metadevice UNIX file system (UFS) logging

For information about Solstice DiskSuite trans metadevice UFS logging, see your Solstice DiskSuite documentation. For information about Solaris UFS logging, see the mount_ufs(1M) man page. provided

The following table lists the logging file systems supported by each volume manager.

Table 1-4 Supported File System Logging Matrix

Volume Manager	Supported File System Logging
Solstice DiskSuite	Solaris UFS loggingSolstice DiskSuite trans metadevice UFS logging,
VERITAS Volume Manager	Solaris UFS logging

Consider the following points when choosing between Solaris UFS logging and Solstice DiskSuite trans metadevice UFS logging for your Solstice DiskSuite volume manager.

• Solaris UFS log size - Solaris UFS logging always allocates the log using free space on the UFS file system, and depending on the size of the file system.

  • On file systems less than 1 Gbyte, the log occupies 1 Mbyte.

  • On file systems 1 Gbyte or greater, the log occupies 1 Mbyte per Gbyte on the file system, up to a maximum of 64 Mbytes.

• Log metadevice - A Solstice DiskSuite trans metadevice manages UFS logging. The logging device component of a trans metadevice is a metadevice that you can mirror and stripe. You can create a maximum 1-Gbyte log size, although 64 Mbytes is sufficient for most file systems. The minimum log size is 1 Mbyte. See your Solstice DiskSuite documentation for information about logging with trans metadevices.