[DERBY-4196] Document initiation of replication from cleanly shut down database

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 10.4.1.3
• Fix Version/s: 10.5.2.0, 10.6.1.0
• Component/s: Documentation, Replication
• Urgency: Urgent
• Assignee: Camilla Haase
• Reporter: Knut Anders Hatlen
• Created: 29/Apr/09 12:19
• Updated: 02/Feb/10 10:04
• Resolved: 14/Jul/09 20:06

Description

The admin guide describes how to start replication.
http://db.apache.org/derby/docs/dev/adminguide/cadminreplicstartrun.html

It describes two steps that must be performed before the database is copied from the master to the slave:

1. Boot the database on the master system
2. Freeze the database (CALL SYSCS_UTIL.SYSCS_FREEZE_DATABASE())

Those two steps could be replaced with a single step:

1-2) Make sure the database on the master system is shut down cleanly

This works because then there is no recovery to be performed when the database later is booted in master mode, and neither the log nor the database will be modified during boot, so the master database will stay completely in sync with the slave.

Advantages with the alternative procedure are:

• no need to keep a process running with the database booted and frozen while copying the database from the master system to the slave system

• uncommitted transactions that are active at the time of the copying won't cause any problems (DERBY-3896)

Issue Links

• is related to: DERBY-3896 Assert failure in LogicalUndoOperation.doMe() when starting slave with uncommitted transactions on the master
• is related to: DERBY-4299 Slave start fails with message that the database is already booted, even when it is not.