Plan for transition
- Last Updated: October 4, 2023
- 5 minute read
- OpenEdge
- Version 12.2
- Documentation
To use transition effectively, you must set all the transition properties. If you do not set the transition properties, full transition processing does not occur. Instead, the extent of transition is limited to changing the role of a database from target to normal. For a complete list of all transition properties, see Transition properties summary.
Plan for transition by making all of the following decisions:
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Which is the primary and which is the secondary database?
To begin transition planning, decide which database is your primary database and which is your secondary database. The primary database is the one on which users initially perform updates.
In the Transition properties, modify the
responsibilityproperty (which is currently used for information purposed only) to identify the type of database. The possible values are primary and secondary. -
What type of transition will occur?
Consider whether the target database will be transitioned to a source database or normal database.
In the Transition properties, set the
database-roleproperty to identify the new role of the database once it is transitioned. Possible values are reverse and normal. If you choose reverse, the role of the database is reversed such that a source database becomes a target database and a target database becomes a source database. If you choose normal, which is the default value, the role of the database becomes that of a normal database, meaning that it is no longer enabled for replication. -
What type of after-imaging functionality should be implemented?
You can choose to start AI automatically on the transitioned database. You can also add AI areas.
In the transition properties, modify the after-imaging properties
auto-begin-ai,auto-add-ai-areas, andai-structure-fileto set AI behavior, as follows:- You can set the
auto-begin-aiproperty value to 0 if you do not want AI to begin automatically after a target-to-source transition. To begin AI automatically after a target-to-source transition, set the value to 1. - You can set the
auto-add-ai-areasproperty to 0 if you do not want to add AI areas to the database automatically (when a database is transitioned to a source database or there are currently no AI areas for the database). To add areas to the database automatically by using the structure file specified in theai-structure-fileproperty (when a database is transitioned to a source database or there are currently no AI areas for the database), set the value to 1. - You can set the name of the structure file (which contains the list of
AI areas to add) in the
ai-structure-fileproperty.
Note: AI may be enabled when a target database transitions to a source database during online failover. - You can set the
- Will database brokers stay online during and after
transition?
During transition, database brokers automatically stay online for both failover and recovery.
After transition, database brokers stay online unless you set the
restart-after-transitionproperty to0.Make sure that you set startup parameters correctly, so that the new source or target databases run with the right configurations. You can also change many parameters while the database is online. For lists of all parameters that you can modify online, see Modify database parameters online using PROMON.
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What types of backup do you want to perform during transition?
Consider what can you accomplish with each backup method, and why it might be advantageous to use one method instead of another method.
In the Transition properties, modify the backup properties
backup-method,backup-arguments, andincremental-backup-argumentsto set the type of backup you want to perform during transition and before AI is enabled, as follows:- You can set the
backup-methodproperty to mark to identify the database as backed up; marking the database as backed up does not allow future AI extents to be used when recovering from a disaster.To back up the database offline by using the OpenEdge PROBKUP utility, set the property to full-offline. The backup is performed in two steps. The first backup is a full backup, which is performed before AI is enabled for the database. The second backup is an incremental backup, which is performed after AI is enabled and after the role of the database is changed.
To back up the database online after the database is restarted, which occurs after the database has been transitioned, set the property to full-online.
- You can set the
backup-argumentsproperty for the arguments required for the full online and offline backups performed for the database.Keep in mind that you must specify, at a minimum, the target file or device in these arguments for both online and offline backups. To avoid overwriting a backup, do not use the same target file or device for both the backup and the incremental backup. Begin the arguments with device-name, and do not use backup validation parameters (such as
-vpand-vf). - You can set the
incremental-backup-argumentsproperty for the arguments required for the offline incremental backup performed after AI is enabled and the database's role is reversed. Begin the arguments with device-name. - If a transition occurs while the databases are online, then the database backup operation automatically becomes online backup. This happens even if you set the transition properties for offline backup.
- You can set the
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Do you want the database to restart automatically after transition?
Think about whether you want to control database startup or have the transition process start the database.
- In the Transition properties, modify the following automatic
transition properties to specify whether the database should be automatically restarted
after transition:
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restart-after-transition -
start-secondary-broker -
source-startup-arguments,target-startup-arguments, ornormal-startup-arguments -
source-secondary-broker-startup-arguments, target-secondary-broker-startup-arguments,ornormal-secondary-broker-startup-arguments
You can set the
restart-after-transitionproperty to 0 if you do not want to restart the database automatically after transition is performed. Set the property to 1 to restart the database automatically after transition is performed. When you specify this value, you must also supply the*-startup-argumentsproperties, or the database startup will fail.Set the
start-secondary-brokerproperty to 1 to start a secondary broker after transition is performed. -
- Set the
*-startup-argumentsproperty or properties as follows:If the database is transitioned to a normal database, specify the
normal-startup-argumentsproperty. These arguments are used when the database is started. The arguments will be appended to the PROSERVE command. In most cases, the only argument specified here should be-pffollowed by a parameter file name, as shown here:-pf db-name.normal.pfIf the database is transitioned to a source database, you must specify the
source-startup-argumentsproperty. The arguments are appended to the PROSERVE command and are used when the database is started. In most cases, the only argument specified should be-pffollowed by a parameter file name, as shown here:-pf db-name.source.pfIf the database is transitioned to a target database, you must specify the
target-startup-argumentsproperty.The arguments are appended to the PROSERVE command and are used when the database is started. In most cases, the only argument specified here should be-pffollowed by a parameter file name, as shown here:-pf db-name.target.pfBecause the database is a target, you must also specify the following argument as an indication to the broker to listen on the TCP/IP port as specified:
-S { port-number | service-name }If the database role is reversed, you must specify the
source-startup-argumentsproperty and thetarget-startup-argumentsproperty.For additional details about the
source-,target-, ornormal-startup-arguments, see Sample of a startup parameter file used by transition .
- In the Transition properties, modify the following automatic
transition properties to specify whether the database should be automatically restarted
after transition:
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Will transition automatically attempt to recover in the event of a
failure?
A backup must exist in order for automatic recovery to occur.
In the Transition properties, modify the
recovery-backup-argumentsproperty, which determines whether transition automatically attempts a recovery. Specify the device name, followed by any other backup arguments.
Once you make each of these decisions, you can set the transition properties accordingly, as described in Set transition properties . (See Transition properties summary for a complete list of all transition properties.)