Transaction log archiving

SnapManager archives transaction log files using NTFS hard links, which enables conservation of disk space in storage systems and improves the system performance.

During a backup operation, SnapManager archives transaction logs on the live file system to the SnapInfo directory. To optimize backup operations in which the Storage Group transaction logs and the SnapInfo directory are on the same NTFS volume, SnapManager archives transaction logs to the SnapInfo directory by creating NTFS hard links instead of performing a file copy operation. This conserves the disk space of the storage system and improves system performance during the transaction log archival phase of the backup operation.

• NTFS hard links
  A hard link is a directory entry for a file, and it serves as a file system-level shortcut to the file. Unlike an application-level link, any updates to the file contents are seen by all applications that access the file using a hard link. Unlike a symbolic link, a hard link created on one NTFS volume cannot point to a file in a different NTFS volume.
• Why SnapManager uses NTFS hard links for transaction log archiving
  By creating NTFS hard links, SnapManager archives transaction log files without physically copying the log file. During a backup operation, SnapManager archives transaction log files on the live file system to the SnapInfo directory, from which the files later can be retrieved, during a restore operation.
• Support for multiple SnapInfo directories
  The main advantage of having multiple SnapInfo directories is the support of NTFS hard links for archiving transaction logs, which helps to free the system resources and disk space. The use of multiple SnapInfo directories also minimizes your exposure to the loss of backups if a SnapInfo directory is lost.