File-System Logging

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

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

• Solaris UFS logging

For information about Solstice DiskSuite trans-metadevice UFS logging, refer to your Solstice DiskSuite documentation. For information about Solaris UFS logging, refer to the mount_ufs(1M) man page and Solaris Transition Guide.

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	Solstice DiskSuite trans-metadevice UFS logging, Solaris 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 - With Solstice DiskSuite trans-metadevice UFS logging, the trans device used for logging creates a metadevice. The log is yet another metadevice that you can mirror and stripe. Furthermore, you can create a maximum 1-Tbyte logging file system with the Solstice DiskSuite software.