Previous Topic

Next Topic

Server Parameters

The Replicator Server has mandatory and optional flags. Mandatory flags must be specified in the configuration file. The mandatory flags are:

All other flags are optional; if you do not set them, default values are used.

Use the Server Startup Settings Worksheet to document your flag settings.

Previous Topic

Next Topic

How the Replication Cycle Works

The replication cycle is a cycle of propagation activity performed by the Replicator Server. This cycle is referred to in some server parameter descriptions.

During the replication cycle, the Replicator Server completes the following tasks:

  1. Checks the status of closed connections to determine whether they must and can be reopened. For more information, see the -ORT flag.
  2. Reads the distribution queue into memory.
  3. Transmits rows to the target databases.
  4. Checks the status of open connections and closes those that have been inactive. For more information, see the -CTO flag.
  5. Waits for the next database event.

Previous Topic

Next Topic

Server Flags

The following table lists each Replicator Server flag, its default, a description of its behavior, and a list of options or associated flags.

Server Flag

Description

Default

-CLQ

(unquiet all targets)

Allows suspended propagation activity to resume for all CDDSs and databases from the local database.

Note: This flag can only be used on a running server from the Performance Monitor in Visual DBA or the Replication Monitor in the Replicator Manager.

For more information, see Server, Database, and CDDS Status.

None

-CTOn

(inactive connection timeout)

Sets time before a connection to a database is terminated due to inactivity.

The options for this flag are:

  • 0 - Does not disconnect for lack of activity
  • n - Connection to a database is terminated after n seconds of inactivity

    The connection to the database is re-established when there is traffic for it, or after the number of replication cycles specified in the -ORT flag (n) have elapsed.

-CTO0

-EMXn

(maximum error)

Sets the maximum error count that this Replicator Server can accumulate before shutting down, where n is a non-negative integer.

For more information, see Error Count Maximum.

-EMX100

-EVTn

(event timeout)

Sets the interval, in seconds, between the beginning of replication cycles.

The options for this flag are:

  • 0 - Server does not wait; it processes replications in response to notifications (default)
  • n - Server begins a new replication cycle every n seconds, where n ranges from 0 to 9,999

    Note: This flag has different effects depending on whether the server is active or in quiet mode. For more information, see -EVTn Flag.

-EVT0

-IDB[vnode::]
dbname

(local database name)

Specifies the name of the local database that the server connects to. If applicable, vnode is the virtual node where the local database resides.

Mandatory
(no default)

-LGLn

(log level)

Sets the level of messages to be written to the replicat.log file. This file is contained in the server home directory.

The options for this flag are:

  • 0 - Silent
  • 1 - Log error messages
  • 2 - Log error and informational messages
  • 3 - Log informational, error, and warning messages (default)

    For more information, see Message Logging.

-LGL3

-MLE

(error mail)

Send mail messages on error to usernames specified in the Error Mail Notification List.

Associated flag:

  • -NML - Do not send error mail.

    For more information, see the Mail Alert Users page in Visual DBA online help or Mail Alert Setup.

-MLE

-MON

(send notifications)

Send activity notifications to any process that is registered to receive them. This setting impacts performance.

Associated flag:

-MON

-NML

(no error mail)

Do not send mail messages on error to usernames specified in the Error Mail Notification List.

Associated flag:

  • -MLE - Send mail to usernames specified in the Mail Alert Users page in the Error Mail Notification List. (default).

    For more information, see the Mail Alert Users page topic in Visual DBA online help or Mail Alert Setup.

-MLE

-NMO

(send no notifications)

Do not send activity notifications to the Performance Monitor in Visual DBA or the Replication Monitor in Replicator Manager. This setting has a positive effect on performance.

Associated flag:

  • -MON - Sends activity notifications to the Performance Monitor in Visual DBA or the Replication Monitor in Replicator Manager (default)

    For more information, see Replication Activity Monitoring.

-MON

-NQT

(unquiet server)

Resumes suspended propagation in the server. The server processes the replication as activity happens on the local database.

Associated flags:

-NQT

-NSR

(check for keys)

Checks for the existence of unique keys in the local and remote databases for tables assigned to the Replicator Server. Checking occurs at Replicator Server startup or when first connecting to a remote database.

Associated flag:

-NSR

-ORTn

(retry opening of
target database)

Sets the number of replication cycles that are to elapse before the server tries to open any target databases that are currently closed.

The options for this flag are:

  • 0 - Does not try to open closed target databases (default)
  • n - Tries to open the connection to the target database after n replication cycles

-ORT0

-OWNowner

(local database owner)

Specifies the owner (DBA) of the local database.

Mandatory
(no default)

-PTLn

(print logging level)

Sets the level of messages to be written to standard output, which is normally redirected to the print.log file. This is a debugging feature.

The options for this flag are:

  • 0 - Silent
  • 1 - Log error messages
  • 2 - Log error and informational messages
  • 3 - Log informational, error, and warning messages (default)

    For more information, see Message Logging.

-PTL3

-QBMn

(queue read limit)

This is a memory throttle, where n is a positive integer between 1 and 999,999. Sets the absolute number of rows that can be read into memory from the distribution queue before the Replicator Server stops reading. The value of -QBM must be greater than or equal to -QBT.

For more information, see Memory Management.

-QBM5000

-QBTn

(transaction break limit)

This is a memory throttle, where n is a positive integer between 1 and 999,999. Sets the maximum number of rows that can be read from the distribution queue before the Replicator Server looks for a logical break in the transaction to maintain consistency. The value of -QBT must be less than
-QBM.

For more information, see Memory Management.

-QBT4000

-QCDn

(quiet CDDS)

Quiets the CDDS where n is the CDDS number; transactions from the local database to the selected CDDS cannot be propagated.

Associated flag:

-UCDn - Unquiets the selected CDDS

For more information, see Server, Database, and CDDS Status.

Not applicable

-QDBn

(quiet database)

Quiets the database where n is the database number; transactions from the local database to the selected database cannot be propagated.

Associated flag:

-UDBn - Unquiets the selected database

For more information, see Server, Database, and CDDS Status.

Not applicable

-QIT

(quiet server)

Quiets the Replicator Server. The Replicator Server ignores notifications that signify activity is taking place in the local database. The Replicator Server only processes replicated transactions as a result of a dd_go_server database event. A quiet server can also process transactions in response to periodic timers set up with the -EVT flag.

Associated flags:

-NQT - Activates the Replicator Server (default)

For more information, see Server, Database, and CDDS Status and Scheduling Servers.

-NQT

SCR

(no key checking)

Specifies that no checking for the existence of unique keys for tables assigned to the server on the local and remote databases occurs upon connection.

Associated flag:

-NSR - Checks for the existence of unique keys at server startup (default)

For more information, see Configuration Errors.

-NSR

-SGL

(single run)

Processes the pending replication transactions and shuts down. This flag permits server scheduling at an operating system level.

For more information, see Server, Database, and CDDS Status, Scheduling Servers, and -SGL Flag.

-NQT

-SVRn

(server number)

The number assigned to a server. The number is determined by the configuration set in Visual DBA or Replicator Manager.

Options for this flag:

  • n - Defines the number of the Replicator Server, where n ranges from 1-999, corresponding to the name of the directory where the server's configuration and log files are located. The number also defines to which targets the Replicator Server transmits.

    The default number of installed servers is 10, but more can be added if events and additional directories are created to support the servers. For more information, see How You Assign Server Numbers Greater Than Ten.

Mandatory
(no default)

-TOTn

(lock timeout)

Allows n seconds before a server can terminate a transaction that is waiting for a lock held by another user.

Options for this flag:

  • 0 - Server waits for a lock indefinitely
  • n - Server waits n seconds, where n ranges from 1 to 999, for a lock.

    A setting of 30 or greater is recommended.

    For more information, see Lock Contention Detection.

-TOT60

-TPCn

(two-phase commit)

Controls whether two-phase commit is used or not. For more information, see Two-Phase Commit.

The options for this flag are:

  • 0 - Two-phase commit is not used to secure a transaction that has been propagated. Uncompleted transactions must be recovered manually from the commit log file.
  • 1 - Two-phase commit is used to secure the propagation of transactions (default)

    Important! Without two-phase commit, there is an increase in the possibility of data integrity problems because of uncompleted transactions.

    For situations where you must use -TPC0, see the appendix "VMS Cluster Support."

-TPC1

-UCDn

(unquiet CDDS)

Enables propagation to a CDDS where n is the CDDS number; transactions from the local database to the selected CDDS can be propagated.

Associated flag:

Not applicable

-UDBn

(unquiet database)

Enables propagation to a database where n is the database number; transactions from the local database to the selected database can be propagated.

Associated flag:

Not applicable

Visual DBA and Performance Monitor: You set flags by expanding the Replication branch in the Performance Monitor window, expanding the desired database, and selecting the desired server. (See the Startup Settings Page topic in Visual DBA or Visual Performance Monitor online help.

Replicator Manager: To set flags using the Replication Monitor, see Edit the Configuration File. Using Replication Monitor, unless otherwise noted, all flags can be set both through database events and directly in the configuration file.

Previous Topic

Next Topic

Server Startup Settings Worksheet

You can use the Server Startup Settings Worksheet to document your server startup parameters. All flags that can be set in the configuration file for startup are listed on the worksheet. You can choose only one flag per category. Unless you specify differently, default values are used. For descriptions of all server parameters, see Server Parameters.

The server information fields on the worksheet are as follows:

The following is an example of the Server Startup Settings Worksheet:

Server Directory:_________________

Local Database Name:____________

Server No:___________________

Database No.:________________

Server Parameter/Behavior

Default

Setting

Server number

-SVR0, -SVRn

Mandatory

 

Local database

-IDB[vnode::]dbname

Mandatory

 

Local database owner

-OWNowner

Mandatory

 

Lock timeout

-TOTn

-TOT60

 

Inactive connection timeout

-CTO0, -CTOn

-CTO0

 

Event timeout

-EVT0, -EVTn

-EVT0

 

Send activity notifIcations

-MON, -NMO

-NMO

 

Retry opening target databases

-ORT0, -ORTn

-ORT0

 

Log messages to stdout

-PTL0, -PTL1, -PTL2, -PTL3

-PTL3

 

Log messages

-LGL0, -LGL1, -LGL2, -LGL3

-LGL3

 

Mail messages on error

-MLE, -NML

-MLE

 

Maximum error count

-EMXn

-EMX100

 

Active quiet

-NQT, -QIT

-NQT

 

Two-phase commit

-TPC0, -TPC1

-TPC1

 

Check unique keys

-NSR, -SCR

-NSR

 

Queue read limit

-QBMn

-QBM50000

 

Transaction break limit

-QBTn

-QBT4000

 

Single-run server

-SGL

None

 

The following illustrates a completed Server Startup Settings Worksheet:


© 2007 Ingres Corporation. All rights reserved.