Overview

This chapter describes CYCLONE, LOGMIRROR and CYFILE.

GOLDILOCKS supports two types of replication, and they are CYCLONE and LOGMIRROR. CYCLONE replicates transactions using CDC, and LOGMIRROR replicates redo log files in the source database.

CYFILE uses CDC method to store/ record the transaction which was applied to the original database in Comma-Separated Values (CSV) format file.

• CYCLONE

  • It uses Change Data Capture (CDC) method to analyze and treat redo log files of the source database, then applies them to a remote database.

  • It supports only asynchronous (async) method because it analyzes contents stored in database's redo log file.

• LOGMIRROR

  • It replicates redo log files stored in the source database to a remote database.

  • It is used to avoid the data loss of CYCLONE which is executed in async method.

• CYFILE

  • It analyzes the redo log file of the database in CDC method, and stores it in CSV format data file.

  • A user can perform the replication by using the corresponding file or perform ETL according to the purpose of the development.

Operating Method

CYCLONE

For more information about general operating method and option, refer to CYCLONE.

Adding and Deleting Nodes

CYCLONE is performed in a group unit, and it is as same as the replication nodes. Add a group when adding nodes, drop a group when deleting nodes.

Examples of Adding Nodes

• Record the group 2 to be added in master configuration file.

  • Set a unique port per each group.

  • The default master configuration file is $GOLDILOCKS_DATA/conf/cyclone.master.conf.

• N/A

  • The following is an example of group 1 node in operation.

...
...
GROUP_NAME = Group1
{
    PORT = 21102
    CAPTURE_TABLE =
    (
        testTable1,
        testTable2
    )
}

• N/A

  • The following is an example of group 2 node to be added.

GROUP_NAME = Group2
{
    PORT = 21103
    CAPTURE_TABLE =
    (
        testTable5,
        testTable6
    )
}

• Record the group 2 to be added in slave configuration file.

  • The port of group 2 should be as same as the port added to the existing master.

  • The default slave configuration file is $GOLDILOCKS_DATA/conf/cyclone.slave.conf.

• N/A

  • The following is an example of group 1 node in operation.

...
...
GROUP_NAME = Group1
{
    PORT = 21102    
    APPLY_TABLE = 
    (
        testTable1 To testTable3,
        testTable2 To testTable4
    )
}

• N/A

  • The following is an example of group 2 node to be added.

GROUP_NAME = Group2
{
    PORT = 21103    
    APPLY_TABLE = 
    (
        testTable5 To testTable7,
        testTable6 To testTable8
    )
}

• Execute and check the added group 2 node in the master device as follows.

prompt> cyclone --master --start --group Group2
[GROUP2] Startup done as Master.

prompt> cyclone --master --status
======================================
|       CYCLONE STATUS - MASTER      |
======================================
 GROUP1 Running...
 GROUP2 Running...
--------------------------------------

• Execute and check the added group 2 node in the slave device as follows.

prompt> cyclone --slave --start --group Group2
[GROUP2] Startup done as Slave.

prompt> cyclone --slave --status
======================================
        CYCLONE STATUS - SLAVE        
======================================
 GROUP1 Running...
 GROUP2 Running...
--------------------------------------

Examples of Deleting Nodes

• Terminate the group 2 node to be deleted in the slave device as follows.

prompt> cyclone --slave --stop --group Group2
stop done.

prompt> cyclone --slave --status
======================================
CYCLONE STATUS - SLAVE
======================================
GROUP1 Running...
--------------------------------------

• Terminate the group 2 node to be deleted in the master device as follows.

prompt> cyclone --master --stop --group Group2
stop done.

prompt> cyclone --master --status
======================================
CYCLONE STATUS - MASTER
======================================
GROUP1 Running...
--------------------------------------

• Drop the group 2 node to be deleted from the master configuration file.

  • The default master configuration file is $GOLDILOCKS_DATA/conf/cyclone.master.conf.

• N/A

  • The following is an example of group 1 node in operation.

...
...
GROUP_NAME = Group1
{
    PORT = 21102
    CAPTURE_TABLE =
    (
        testTable1,
        testTable2
    )
}

• N/A

  • The following is an example of deleting group 2 node.

GROUP_NAME = Group2
{
    PORT = 21103
    CAPTURE_TABLE =
    (
        testTable5,
        testTable6
    )
}

• Drop the group 2 node to be deleted from the slave configuration file as follows.

  • The default slave configuration file is $GOLDILOCKS_DATA/conf/cyclone.slave.conf.

• N/A

  • The following is an example of group 1 node in operation.

...
...
GROUP_NAME = Group1
{
    PORT = 21102    
    APPLY_TABLE = 
    (
        testTable1 To testTable3,
        testTable2 To testTable4
    )
}

• N/A

  • The following is an example of deleting group 2 node.

GROUP_NAME = Group2
{
    PORT = 21103    
    APPLY_TABLE = 
    (
        testTable5 To testTable7,
        testTable6 To testTable8
    )
}

Initializing Replication

Initializing replication is executed when existing replication nodes or a group's table gives up execution due to DDL operation. A specific node or entire node can be initialized.

The initializing replication is performed by restarting replication being operated in slave using --reset option.
On the other hand, master does not require any operation.

Examples of Initializing Replication on a Specific Node

• Terminate the group 2 node to be initialized in the slave device as follows.

prompt> cyclone --slave --stop --group Group2
stop done.

prompt> cyclone --slave --status
======================================
        CYCLONE STATUS - SLAVE        
======================================
 GROUP1 Running...
--------------------------------------

• Restart group 2 node in slave device using --reset option.

  • Master device does not require any operation.

  • Replication restarts from the current point.

prompt> cyclone --slave --start --reset --group Group2
[GROUP2] Startup done as Slave.

prompt> cyclone --slave --status
======================================
        CYCLONE STATUS - SLAVE        
======================================
 GROUP1 Running...
 GROUP2 Running...
--------------------------------------

Examples of Initializing Replication of All Nodes

• Terminate all CYCLONE in operation in the slave device as follows.

prompt> cyclone --stop --slave

• Restart CYCLONE in slave device using --reset option.

  • Master device does not require any operation.

  • Replication starts from the current point.

prompt> cyclone --slave --start --reset
[GROUP1] Startup done as Slave.
[GROUP2] Startup done as Slave.

prompt> cyclone --slave --status
======================================
        CYCLONE STATUS - SLAVE        
======================================
 GROUP1 Running...
 GROUP2 Running...
--------------------------------------

LOGMIRROR

For more information about general operation method and options, refer to LOGMIRROR.

Retrieving LOGMIRROR State

GOLDILOCKS includes the response waiting procedure of LOGMIRROR when GOLDILOCKS interworks with LOGMIRROR. If LOGMIRROR is waiting for response, GOLDILOCKS is also waiting in a blocked state. This state can be retrieved in v$system_stat.

gSQL> SELECT * FROM V$SYSTEM_STAT WHERE STAT_NAME='LOG_MIRROR_SYNC_STATE';

STAT_NAME             STAT_VALUE COMMENTS                                     
--------------------- ------ ---------------------------------------------
LOG_MIRROR_SYNC_STATE      0 logmirror sync state( 0 : sync, 1 : blocked )


1 row selected.

If STAT_VALUE is 0, it is not a standby state but an ordinary state. If STAT_VALUE is 1, it is a blocked state waiting for a response. To restart GOLDILOCKS service while LOGMIRROR is waiting for a response, LOGMIRROR service can be stopped by modifying LOG_MIRROR_TIMEOUT as follows.

gSQL> ALTER SYSTEM SET LOG_MIRROR_TIMEOUT = 20;

System altered.

Initializing Replication

Initializing replication of LOGMIRROR should be done manually. This is to prevent data dropping or the unrecoverable situation driven by the user's incorrect option usage.

Examples of Initializing Replication

• Terminate LOGMIRROR in operation in the slave device as follows.

prompt> logmirror --slave --stop 
stop done.

• Terminate LOGMIRROR in operation in the master device as follows.

prompt> logmirror --master --stop 
stop done.

• Drop the replicated control files and redo log files from the slave device.

  • For more information about the path, refer to 'LOG_PATH' option described in the slave configuration file.

  • The default LOGMIRROR slave configuration file is $GOLDILOCKS_DATA/conf/logmirror.slave.conf.

CYFILE

For more information about how to operate and its options, refer to CYFILE.

Starting, Stopping and Status Checking of cyfile

Example

• Start cyfile from the current moment by using the default configuration file.

prompt> cyfile --start --reset all
Startup done.

• Stop cyfile.

prompt> cyfile --stop
Stop done.

• CYFILE is operated in groups and the data file is created in groups.

prompt> cyfile --status
cyfile --status
======================================
|          CYFILE STATUS             |
======================================
 GROUP1 Running...
======================================

Trace Log

The followings are detailed information about the trace log.

Troubleshooting of CYCLONE

The followings are error messages and troubleshooting of CYCLONE.

Troubleshooting of LOGMIRROR

The followings are error messages and troubleshooting of LOGMIRROR.

Troubleshooting of CYFILE

The followings are error messages and troubleshooting of CYFILE.