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6 Multi-Master Replication Operation : 6.3 Creating Additional Master Nodes

Step 1: Make sure the database server for the master definition node is running and accepting client connections.
Step 2: Select the MMR type node under the same Publication Server node that contains the master definition node. From the Publication menu, choose Publication Database, and then choose Add Database. Alternatively, click the secondary mouse button on the MMR type node and choose Add Database. The Publication Service – Add Database dialog box appears.
Step 3: Fill in the following fields:
Database Type. Select PostgreSQL or Postgres Plus Advanced Server for the master node. For an Advanced Server Oracle compatible installation, select the Postgres Plus Advanced Server option. For PostgreSQL or an Advanced Server PostgreSQL compatible installation, select the PostgreSQL option.
Host. IP address of the host on which the master node is running.
Port. Port on which the master node is listening for connections.
User. The database user name for the master node created in Step 1 of Section 6.1.4.
Password. Password of the database user.
Database. Enter the database name of the master node.
URL Options (For SSL connectivity). Enter the URL options to establish SSL connectivity to the master node. See Section 7.11 for information on using SSL connections.
Changeset Logging (For Postgres). This setting is predetermined by the selection on the master definition node (see Section 6.2.2). Table Triggers is for the trigger-based method of synchronization replication. WAL Stream is for the log-based method of synchronization replication. See Section 2.2.9 for information on the trigger-based method. See Section 2.2.10 for information on the log-based method.
Node Priority Level. An integer from 1 to 10, which is the priority level assigned to this master node for conflict resolution based on node priority. The highest priority is 1 while the lowest is 10. See Section 6.6.4 for information on conflict resolution strategies. As each additional master node is added, the default priority level number increases assigning a lower priority level to each additional node.
Replicate Publication Schema. Check this box if you want the publication server to create the publication table definitions in the new master node by copying the definitions from the master definition node. If you do not check this box, it is assumed that you have already created the table definitions in the master node. If you are using the offline snapshot technique to create this master node, do not check this box. See Section 7.9 for information on using an offline snapshot.
Perform Initial Snapshot. Check this box if you want the publication server to perform a snapshot from the master definition node to this master node when you click the Save button. If you do not check this box, the tables on the master node will not be loaded until you perform a replication at some later time. If you are using the offline snapshot technique to create this master node, you should have already loaded the table rows. Therefore do not check this box unless you want to reload the data. See Section 7.9 for information on using an offline snapshot.
Note: Unless you intend to use the offline snapshot technique (see Section 7.9), it is suggested that you check the Perform Initial Snapshot box. An initial snapshot replication must be performed from the master definition node to every other master node before performing synchronization replications on demand (see Section 6.5.2) or by a schedule (see Section 7.2). If a newly added master node did not undergo an initial snapshot, any subsequent synchronization replication may fail to apply the transactions to that master node. The initial snapshot can also be taken by performing an on demand snapshot (see Section 6.5.1).
Step 4: Click the Test button. If Test Result: Success appears, click the OK button.
Step 5 (Optional): If you defined a set of available table filters for the publication, you have the option of enabling these filters on this master node. See Section 6.2.3 for instructions on defining table filters. If you do not wish to filter the rows that are replicated to this master node, go to Step 6.
Note: See Section 2.2.12.3 for table setup requirements for a log-based replication system as well as general restrictions on the use of table filters.
In the following example the filter named dept_10_20_30 is enabled on the dept table and the filter named dept_30 is enabled on the emp table of this master node.
Step 6: Check the Perform Initial Snapshot box if you want the publication server to perform a snapshot from the master definition node to this master node when you click the Save button. If you do not check this box, the tables on the master node will not be loaded until you perform a replication at some later time.
Unlike the master definition node, the label MDN does not appear at the end of the node in the replication tree. The MDN field is set to No in the Property window to indicate this is not the master definition node.
Step 7: If you expect update/update conflicts, then set the REPLICA IDENTITY option to FULL on those tables where the conflicts are expected to occur. See Section 6.6.1 for additional information.
Step 8 (Optional): If users are to access the data in the publication tables residing on this master node, it is convenient to have one or more “group” roles containing the required privileges to access these tables. For the trigger-based method, privileges must also be granted on the control schema objects to users who are to perform inserts, updates, or deletions on the publication tables. When using the log-based method a user needs access to the publication tables and to certain control schema objects as well under certain circumstances.

6 Multi-Master Replication Operation : 6.3 Creating Additional Master Nodes

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