Preparing to back up data

Before you back up storage spaces and logical logs, you must prepare the system and copy critical administrative files.

Procedure

To prepare to back up data:
  1. Configure ON-Bar and your storage manager.
  2. Ensure that you have enough logical log space.
    ON-Bar checks for available logical-log space at the beginning of a backup. If the logs are nearly full, ON-Bar backs up and frees the logs before attempting to back up the storage spaces. If the logs contain ample space, ON-Bar backs up the storage spaces, then the logical logs.
  3. Verify that you have enough temporary disk space.
    The database server uses temporary disk space to store the before images of data that are overwritten while backups are occurring and overflow from query processing that occurs in memory. Verify that the DBSPACETEMP environment variable and DBSPACETEMP configuration parameter specify dbspaces that have enough space for your needs. If there is not enough room in the specified dbspaces, the backup will fail, root dbspace will be used, or the backup will fail after filling the root dbspace.
  4. Back up administrative files to a different location.
  5. Run the oncheck -cD command to verify that all database server data is consistent.
    You do not need to check for consistency before every level-0 backup. Do not discard a backup that is known to be consistent until the next time that you verify the consistency of your databases.