Defining Devices for ON-Archive with SAP Scripts (SAP Library - SAP Database Guide: Informix (BC-DB-INF-DBA))

Defining Devices for ON-Archive with SAP Scripts

Use

This procedure describes how to define devices for ON-Archive with the Informix database if you are using the SAP scripts. You define devices in the config.arc file. The device names given in this procedure are as required by the SAP scripts.

Follow this procedure before you start performing archives, backups, and restores of your database.

Caution

Check your Informix release notes for valid tape devices or other restrictions.

Procedure

Log on as user informix using the following command:

su - informix

Open the config.arc file, which you can normally find in the $INFORMIXDIR/etc directory. If the file is not in this directory, see the note in Editing the config.arc File for ON-Archive.

The physical device names (for example, /dev/rmt/1hc ) given in the following steps are examples only. However, you must use the logical device names (for example, DBTP1_VOP ) given, since these are expected by the SAP scripts.

Enter a tape device for archive:

DEVICE DBTP1_VOP = /dev/rmt/1hc

Enter a tape device for logical-log backup:

DEVICE LOGTP1_VOP = /dev/rmt/0hc

Enter a tape device for emergency logical-log backup and logs salvage (this example uses the same physical device as for normal logical-log backup):

DEVICE DATARTR_VOP = /dev/rmt/0hc

For a summary what you can do to avoid emergency logical-log backups, see Preventing Emergency Logical-Log Backup.

Note

You can specify multiple physical tape devices for a logical device, for example:

DEVICE LOGTP1_VOP = /dev/rmt/0hc, /dev/rmt/1hc
DEVICE DBTP1_VOP = /dev/rmt/2hc, /dev/rmt/3hc

This has the following advantages:

If a particular physical device fails, you can switch to the next one in the sequence.

If the tape on the first physical device fills up, and there is a tape already mounted on the next physical device, it is used and processing can proceed without delay.

Note

To do parallel archives (used in large installations to speed up the process), you must define additional logical devices. If you want to add extra logical devices for parallel archive, see Defining Devices for ON-Archive Without SAP Scripts. In this case, you can still use the SAP scripts as described above to define the volumes for the basic set of devices.

When you have finished editing device names in the config.arc file, you need to restart the ON-Archive cataloger for the changes to take effect. Enter the following from the command line (it does not matter if the cataloger is already running):

$ stop_oncatlgr

$ start_oncatlgr

Result

You have now completed one of the steps required to configure ON-Archive for performing archives, backups, and restores of your database. When you set up volume sets and volumes using the SAP scripts, the device names given in this procedure are used. Refer to Setting Up Volume Sets and Volumes for ON-Archive with SAP Scripts.

See also:

Configuration Files for ON-Archive

Defining Devices for ON-Archive Without SAP Scripts

Informix documentation at http://www.informix.com