Using Command Central to Manage Terracotta

Software AG Command Central is a tool that release managers, infrastructure engineers, system administrators, and operators can use to perform administrative tasks from a centralized location. It assists with configuration, management, and monitoring tasks in a simple and flexible manner.

Terracotta server instances can be managed from Command Central like other Software AG products. Both the Command Line and Web Interfaces of Command Central are supported.

Terracotta supports the following Command Central CLI (Command Line Interface) commands:

sagcc list inventory components : Lists information about run-time components.

sagcc get inventory components : Retrieves information about a specified run-time component.

sagcc exec lifecycle : Executes a lifecycle action against run-time components. See Lifecycle Actions for Terracotta for Terracotta-specific information about Lifecycle Actions.

sagcc get monitoring state : Retrieves the run-time status and run-time state of a run-time component.

sagcc get monitoring alerts : Lists the alerts for a specified run-time component.

sagcc get monitoring runtimestatus : Retrieves the run-time status of a run-time component.

sagcc get configuration data : Retrieves data for a specified configuration instance that belongs to a specified run-time component.

sagcc list configuration types : Lists information about configuration types for the specified run-time component. See Supported Configuration Types for Terracotta-specific information about configuration types.

sagcc list configuration instances : Retrieves information about a specific configuration instance that belongs to a specified run-time component.

sagcc list diagnostics logs : Lists the log files that a specified run-time component supports.

sagcc get diagnostics logs : Retrieves log entries from a log file. Log information includes the date, time, and description of events that occurred with a specified run-time component.

For information about Command Central CLI commands, see the Command Central Help.

Terracotta supports creating instances of the following configuration types:

JVM-OPTIONS: The JVM memory settings for the Terracotta Server instance in JAVA_OPTS environment variable format.

TC-SERVER-NAME: The name for the Terracotta Server instance. Editing this property is not allowed.

Terracotta supports the following lifecycle actions with the sagcc exec lifecycle CLI command and the Command Central Web Interface:

Terracotta can return the following statuses from sagcc get monitoring runtimestatus and sagcc get monitoring state CLI commands and the Command Central Web Interface:

The server is a slave (Passive) synchronizing with its master (Active).

Not Ready: The server is not ready to accept client requests. To make it ready, follow the steps defined in the section Making server ready.

Online Master: The server instance is running and is the master (Active) in its stripe.

Online Slave: The server instance is running and is a slave (Passive) in its stripe.

Failed: The server instance was running, but crashed or was killed without the SPM plugin's knowledge. If the server had crashed, checking its logs may help uncover the reason.

Unknown: The state of the server instance is not known. This is most likely because of an unexpected exception or error that occurred while trying to fetch the server status.

The Terracotta server and SPM related files can be found under ${INSTALL_ROOT}/TerracottaDB/server/SPM. This directory contains the following:

Contains the Terracotta config file cluster.properties. If any changes to the configuration are required, such as increasing the offheap, this file needs to be updated manually. See the Updating the config file section for more details.

Contains data maintained by Terracotta server. The contents of this directory are useful for troubleshooting problems with the server. The table below summarizes the contents of this directory:

Directory	Description
logs	Contains Terracotta server logs
metadata	Contains Terracotta server metadata
user-data	Contains Terracotta client data
config	Contains Terracotta server configuration repository

A Terracotta configuration file is a Java properties file containing configuration and topology information of the entire Terracotta cluster. Any changes to the config file must be done manually.

To find out more, visit The TerracottaConfiguration File.

Configuration changes in the default configuration cluster.properties file can be done freely before cluster activation. It's advised to make all the important changes before activating the cluster. After the cluster has been activated, the configuration can still be changed, but that's subject to certain constraints.

To find out more, visit Performing configuration changes.

Topology changes in the default configuration cluster.properties file can be done freely before cluster activation. If the configuration of a new node is added to this file, remember to use the same file across all installations. Also, the server name for the current installation must be updated in the server-name file (located next to cluster.properties).

The cluster topology can be changed dynamically as well.

To find out more, see attaching nodes dynamically and detaching nodes dynamically in the description of the config tool.

When the Terracotta server is started for the first time from Command Central, it will be in the 'Not Ready' state. To make the server ready to accept client requests, it needs to be part of an activated cluster. The activate command of the config tool (located under ${INSTALL_ROOT}/TerracottaDB/tools/bin) can be used to activate the cluster.