Saving the Shadow Database

This procedure saves the Shadow Database to tape and gives you the choice of maintaining the live database active throughout. After completing the save and verifying it, the Shadow Database is disabled.

Notes:

This procedure is not the recommended way of backing up a 24 hour database on a regular basis. Instead, it is recommended that you save the live database, to minimise the length of time both databases are enabled and so exposed to system failure.
This procedure must be carried out from the live database.
Transaction logging must be active.
The mechanism for enabling and disabling databases is different on UNIX and Windows. Refer to Shadow Database Host Configuration.

Procedure

Select option 8 on the Routine Maintenance menu. A message is then displayed describing the purpose of the procedure and prompting you to confirm that you wish to continue.
After entering y at the confirmation prompt, you are asked
```
Do you want to disable the live database partition

during this procedure (y/n/q) ? :
```
Caution

If you enter n and carry out this procedure while the live database is active, database resilience may be significantly reduced until the procedure is completed and the Shadow partition is disabled again.

If the system crashes while both live and Shadow Databases are active, both databases will be corrupted and a complete restore of the last database save and subsequent clean logs will be necessary on both databases.

Enter y to log off all users from the live database and disable the live partition. This will protect your live database from being corrupted if the system crashes while the save of the Shadow is being carried out.
The Shadow partition is now enabled and the save set up procedure initiated. First you are asked:
```
Do you want to suppress the VERIFY-SAVE following 

the Save (y/n/q) ? :
```
Caution

The integrity of the save cannot be guaranteed if you suppress VERIFY-SAVE.

Enter n to enforce verification or y to omit verification. If you enter y, a warning prompt is displayed asking you to confirm that you wish to carry out the save without verifying it.

Having made the appropriate responses:

If the Physical Save or dbsave option was selected when defining the backup method used by tlmenu, go to step 5.

If the FILE-SAVE method was selected, you are first prompted to set up tape parameters for the FILE-SAVE. You must respond to each prompt to move on to the next one. The sequence of prompts is, as follows:

Will FILE-SAVE be multi-reel, if unsure select yes (y/n/q) ? :

Note: If you enter y, you will be prompted for multiple tape units during this FILE-SAVE setup sequence.

Enter tape record block length (if other than 16000, the default) :

The following tapes are available on the Shadow Database:
Tape Unit Status
Unit   Type   Status      Port    Channel  Assigned   Assigned Buffs  Reel
number                    number  name     blocksize  density
 1     QIC    Available
 2     8mm    Available

Enter LOCAL tape unit number for Save (tape_unit) :

Enter LOCAL tape unit number for Save (tape_unit), in sequence,

separated by commas : (if multi-reel save selected)

Enter tape density (if other than Device Default) :

Enter tape label if desired :

You are then prompted to specify the time for the save to start.
```
Enter start time for save (hh:mm) or return for immediate start :
```
Enter the time in the format hh:mm at which you want the save to start. A new clean log is created and logging is switched to the new clean log.
When using the FILE-SAVE method, a message similar to the following is displayed.
```
About to start the FILE-SAVE on shadow tape unit(s) n,
 using tape record block length nnnnn,
tape density DEFAULT, tape label file-save,
with a start time of hh:mm.
Are you ready to start the Save (y/n/q) ? :
```
For a dbsave the following message is displayed:
```
About to start dbsave with a start time of hh:mm

Are you ready to start the Save (y/n/q) ? :
```
- Enter y to start the save. This displays the message:
```
Now starting shadow save...
```
  The save sequence is then executed. If you entered a time, the tape devices will be assigned, then the save will go to sleep until that time.
- Enter n to repeat the tape parameters setup sequence (step 4).

On completing the save and verify procedures successfully, the tape device is detached from the database, the live database is enabled again, if necessary, and the Shadow Database is disabled.

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