You need to set up storage devices – for example, tape drives – for logical-log backup of your Informix database with ON-Bar .

1. Decide the number of storage devices.

SAP recommends that you have at least two storage devices, one for database backups and one for logical-log backups. Otherwise, if your logical logs fill up when you are performing a logical-log backup, the database might stop processing. At the minimum, you must have one storage device for logical-log backup.

2. Consider the speed and capacity of storage devices.

Your devices must be fast enough to cope with the maximum rate at which the logical log fills. Your devices must also accept storage media with sufficient capacity for your logical-log backups. Local devices are more likely to cope than remote devices.

3. If using continuous logical-log backup, dedicate a storage device.

SAP recommends you to dedicate a local device for logical-log backup because the performance and security is better than with a remote device.

4. Define your storage devices.

You need to define at least the device LTAPEDEV with a suitable physical device. Refer to Configuring ON-Bar.



Do not use /dev/null (UNIX) or nul (NT) for LTAPEDEV if you want to perform a restore of your system up to the time of failure.

ON-Bar does not use LTAPEDEV to specify the storage device for logical-log backup. However, if you specify a null value for LTAPEDEV , the logical-log files are marked as "backed up" as soon as they are full. Therefore, they cannot be backed up and the transactions recorded in these logs cannot be used for a logical restore.

5. Make sure that storage devices are correctly set up with your storage manager.

Your have chosen storage devices for optimal logical-log backup with ON-Bar .

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