On Linux systems, start SharePlex by running the sp_cop program. After you activate a configuration, sp_cop spawns the necessary child replication processes on the same system. Each instance of sp_cop that you start is a parent to its own set of child replication processes. The sp_cop process must be started on each system that is part of the replication configuration.

You can start sp_cop in one of two ways:

• From the operating system command line.
• At system startup as part of the startup file.

IMPORTANT: Run SharePlex from either the korn (ksh) or C shell (csh) shell.

Warning! Do not use the Bourne shell (sh), because the way it handles background processes is not compatible with SharePlex. If you must use the Bourne shell, switch shells to ksh or csh to run SharePlex, then exit the shell and return to the Bourne shell.

Start SharePlex on Linux

To start SharePlex, you must log onto the system as a SharePlex Administrator. Your user name must be assigned to the SharePlex admin group in the /etc/group file. For more information, see Assign SharePlex users to security groups in the SharePlex Administrator's guide.

Table 3: SharePlex startup syntax

Method	Startup syntax
From root, with full path	$ /productdir/bin/sp_cop [-uidentifier] &
CD to the product directory	$cd /productdir/bin $./sp_cop [-uidentifier] &
From a startup script	#!/bin/ksh cd productdir\bin nohup sp_cop [-uidentifier] &

Table 4: Description of SharePlex startup syntax

Argument	Description
&	Causes SharePlex to run in the background.
nohup	Directs the startup of SharePlex to continue in the background after the current user logs out.
-uidentifier	Starts sp_cop with a unique identifier. Use this option when there are multiple instances of sp_cop running on a system, which is required for some SharePlex configurations. For more information, see Run multiple instances of SharePlex in the SharePlex Administrator Guide. Some suggestions for identifier are: the SharePlex port number (such as -u2100) the identifier of the database for which replication is running (such as -pg13c) any descriptive identifier (such as -utest)

Identify SharePlex processes on Linux

Every session of sp_cop has a process ID number. The ID is returned after startup and then the command prompt reappears. If a configuration was activated during a former session of sp_cop, replication begins immediately. Without an active configuration, sp_cop runs passively in the background.

On Linux systems, you can use the ps -ef | grep sp_ command to view the SharePlex processes that are running.

• The sp_cop process is the root process.

• The following child processes are spawned by sp_cop on a source system:

  • Command and Control process (sp_cnc)
  • Capture (sp_ocap)
  • Read (sp_ordr)
  • Export (sp_xport)

• The following child processes are spawned by sp_cop on a target system:

  • Command and Control process (sp_cnc)

  • Import (sp_mport)
  • Post (sp_xpst)

Each child process has the same -uidentifier as its parent sp_cop process. This makes it easier to identify related processes when multiple session of sp_cop are running.

Stop SharePlex on Linux

Before shutting down the SharePlex process user should deactivate the active configuration and check the following processes:

• Capture/read/export on source
• Import/post on target are not running

For more information on this, see the Deactivate Config in the SharePlex Reference Guide.

To stop SharePlex, issue the shutdown command in sp_ctrl. This is a graceful shutdown that saves the state of each process, performs a checkpoint to disk, read/releases buffered data, and removes child processes. Data in the queues remains safely in place, ready for processing when sp_cop starts again. The shutdown process can take some time if SharePlex is processing large operations.

You can use the force option with the shutdown command to forcefully shut down replication if necessary. It terminates sp_cop immediately, bypassing normal shutdown procedures. See the SharePlex Reference Guide for more information about this command.

Shutdown considerations on Linux

You can safely shut down SharePlex for a short time while there is still transactional activity. The next time you start SharePlex, replication resumes at the correct place in the WAL files, if needed. However, the best practice is to leave SharePlex running while there is transactional activity. Otherwise, SharePlex may need to process a large volume of WAL files backlog when you start it again, and there will be latency between the source and target data.

Note: If you want to shut down both SharePlex and the database, shut down SharePlex first. Otherwise, SharePlex will interpret that the database is failing and generate a warning message.

As an alternative to stopping SharePlex, you can use the stop command in sp_ctrl to stop individual SharePlex replication processes as needed. See the SharePlex Reference Guide for more information about this command.