Disaster Recovery

In Tamino, disaster recovery stands for the restoration of a Tamino database when everything is lost except for a backup of the database and recovery files. This may be the case after a total loss of the computing environment, in which backup and recovery files are still available on an archive. Unlike the normal restore and recover process, no information about the locations of the recovery files exists within the internal configuration store. Nevertheless, Tamino offers the possibility to recover from this disaster scenario if the following conditions are met:

The log spaces since the last backup used to create a database must be complete (no log space must be missing).
All log spaces must be accessible.
The log spaces must not have been used for a Recover until or Skip recover process before.

In order to meet these conditions, you should have a good archiving concept. Please contact Software AG Support, if you require support for this task.

The following two disaster recovery scenarios are described in this document:

Recovering from Internal Configuration Store Corruption
Recovering from the Loss of the Host Environment

Recovering from Internal Configuration Store Corruption

If the content of your internal configuration store (registry) is damaged for any reason (e.g. someone has accidentally deleted the information, or a disk error has occurred), you will not be able to access the Tamino databases. However, the file Registry.log keeps track of all internal configuration store entries that are relevant to Tamino and have occurred since the last installation of Tamino.

On Windows

To recover from registry corruption

Use the import file provided by the installation of the latest Tamino version

regutil delete "HKLM\Software AG\Tamino"

regutil import "<DRIVE_LETTER>:\Documents and Settings\All Users\Application Data\Software AG\Tamino\Registry.export"
Apply the internal configuration store entries from the saved log with

regutil -f "<DRIVE_LETTER>:\Documents and Settings\All Users\Application Data\Software AG\Tamino \Registry.log"

On UNIX

Case 1: A backup of $SAG/common/rgs/REGFILE is available

Restore the backup of the internal configuration store

$SAG/common/rgs/REGFILE
Apply the internal configuration store entries from the saved log with

regutil -f "$SAG/ino/Registry.log"

Case 2: A backup of $SAG/common/rgs/REGFILE is not available

Save the file "$SAG/ino/Registry.log"
Reinstall Tamino, including the internal products.
Apply the internal configuration store entries from the saved log with

regutil -f <saved Registry.log>

Note:
Note that the backup file of the Registry.log must be a backup of the current Tamino installation, and not of a former version of Tamino.

Recovering from the Loss of the Host Environment

If you have lost your total computing environment due to a disaster, it is still possible to recover if a backup and all subsequent recovery files are available. However, the recovery files must not have been used for a restore with no full recover (recover with Skip Recover or Recover Until) process. The steps for disaster recovery in this case are:

To recover from the loss of the host environment

In a new computing environment, install Tamino.
Perform a Create from Backup with the given backup file.

Note:
The backup file you specify must be a full backup file. You cannot use an incremental backup file to perform this step.

If no recovery files are to be applied or available, this is all that needs to be done. This may be the case if you are doing frequent backups.

If recovery files are available, apply them by following the next steps:

Add the internal configuration store entries for the recovery files.

To do so, create a script using the regutil utility to add the entries for the recovery files. An entry for a log space (with the extension .1LO) has the following structure:

HKEY_LOCAL_MACHINE
\SOFTWARE
 \Software AG
  \Tamino
   \servers
    \<database name>
     \savepoints
      \000000000000
       \log space
        \<session number>
         \<extent number>

The session number must be extended by leading zeroes as a 10 digit number, the extent number as a 5 digit number.

Here is an example: Two log spaces, AAF000010000000025.1L0 and AAF000010000000026.1L0 on the directory D:\archive, are to be processed.

create		"HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000\log space"

create	      "HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000\log space\00025"

create	      "HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000\log space\00025\00001"

setvaluedata "HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000
              \log space\00025\00001" type "file"

setvaluedata "HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000
              \log space\00025\00001" path "D:\archieve\AAF000010000000025.1L0"

create	      "HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000
              \log space\00026"

create       "HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000
              \log space\00026\00001"

setvaluedata "HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000
              \log space\00026\00001" type "file"

setvaluedata "HKLMS\Software AG\Tamino\servers\db1\savepoints\000000000000
              \log space\00026\00001"  

path	        "D:\archieve\AAF000010000000026.1L0"

Other recovery files than log spaces (extension .1L0) only exists when the Tamino Data Loader was used without the concurrentWrite option. These are files with an extension of .1C0, .1C1 or .1C2. In case you want to do a disaster recovery with Tamino Data Loader recovery files, please contact Software AG Support to ask how to add registry entries.

Use the Restore/Recover function.

Note:
Note that the server must not be started between Create from Backup and performing the recover function.