High Availability:Software:Configuration Database - Revision history

Cbilodeau: fix typo

2010-01-14T16:59:25Z

fix typo

Cbilodeau: add control network recommendation for database connection.

2010-01-14T16:53:24Z

add control network recommendation for database connection.

Cbilodeau: improve switchover description

2010-01-05T15:53:04Z

improve switchover description

Cbilodeau: add solution developer warnings and reference

2010-01-05T15:46:27Z

add solution developer warnings and reference

Cbilodeau: improve description

2010-01-05T15:07:25Z

improve description

New page

The [[Toolpack]] configuration is located in a MySQL database.

== High Availability ==

=== Database Connection ===

Since [[Toolpack]] is not necessarily running on the same host as the MySQL database, it uses sockets to connect to the database. To increase the reliability, [[Toolpack]] uses 2 database connections. If one becomes unavailable(example network is down), [[Toolpack]] can still connect to the database using the other sub net.

=== Database Replication ===

To protect against a loss of database, [[Toolpack]] uses the MySQL database replication feature. In a typical 2 hosts redundancy setup, the [[Primary/Secondary|primary]] and [[Primary/Secondary|secondary]] hosts will run a [[Toolpack]] system and a MySQL database. At start up, [[Toolpack]] will configure one database as [[Master/Slave|master]] database, the other as [[Master/Slave|slave]]. Once the database configuration is done the [[Master/Slave|master]] database will copy itself in the [[Master/Slave|slave]] database. After that, any changes made on the [[Master/Slave|master]] database will then get replicated on the [[Master/Slave|slave]] database.

The following figure illustrates the database setup in a high availability system:

[[Image:DB_HA_Prim_master.png|widthpx|High available Toolapck system with the master database on the primary host]]

It is interesting to note that both Toolpack system always access the same database.

The next image shows a database [[Switchover |switchover]]:

[[Image:DB_HA_Sec_master_No_Prim.png|widthpx|High available Toolapck system with the master database on the secondary host after a switchover]]

When the [[Primary/Secondary|primary]] database becomes available again, [[Toolpack]] sets it as replication [[Master/Slave|slave]]. There is no database switch back as illustrated with the following image:

[[Image:DB_HA_Sec_master.png|widthpx|High available Toolapck system with the master database on the secondary host]]

@@ Line 6: / Line 6: @@
 === Database Connection ===
-Since [[Toolpack]] is not necessarily running on the same host as the MySQL database, it uses sockets to connect to the database. To increase the reliability, [[Toolpack]] uses 2 database connections. If one becomes unavailable(example network is down), [[Toolpack]] can still connect to the database using the other sub net. It is recommended to use the [[Toolpack]] control network for the database connection.
+Since [[Toolpack]] is not necessarily running on the same host as the MySQL database, it uses sockets to connect to the database. To increase the reliability, [[Toolpack]] uses 2 database connections. If one becomes unavailable(example network is down), [[Toolpack]] can still connect to the database using the other sub net. It is recommended to use the [[Toolpack]] control network sub net for the database connection.
 === Database Replication ===

@@ Line 18: / Line 18: @@
 It is interesting to note that both Toolpack system access the same database.
-The next image shows a database [[Switchover |switchover]]:
+The next image shows a database [[Switchover |switchover]], since the primary database is lost, the secondary database becomes master and both [[Toolpack]] interacts with the new master database:
 [[Image:DB_HA_Sec_master_No_Prim.png|widthpx|High available Toolapck system with the master database on the secondary host after a switchover]]

@@ Line 16: / Line 16: @@
 [[Image:DB_HA_Prim_master.png|widthpx|High available Toolapck system with the master database on the primary host]]
-It is interesting to note that both Toolpack system always access the same database.
+It is interesting to note that both Toolpack system access the same database.
 The next image shows a database [[Switchover |switchover]]:
@@ Line 23: / Line 23: @@
-When the [[Primary/Secondary|primary]] database becomes available again, [[Toolpack]] sets it as replication [[Master/Slave|slave]]. There is no database switch back as illustrated with the following image:
+When the [[Primary/Secondary|primary]] database becomes available again, [[Toolpack]] sets it as replication [[Master/Slave|slave]]. There is no database switch back as illustrate with the following image:
 [[Image:DB_HA_Sec_master.png|widthpx|High available Toolapck system with the master database on the secondary host]]