Configuration Overview

If multiple components of different applications need to be deployed in different environments, each component must be configured based on the environment and application when you create or upgrade them. This is complex and error-prone. If the component configuration is incorrect, the deployment or upgrade will fail, which severely affects services.

To solve the preceding problems, ServiceStage provides configuration management. By creating a unified configuration, you can fill the system variables (such as the IP address, port number, database address, and application name associated with the environment) of the component environment and application in the configuration to generate a configuration file. When a component is associated with a configuration file for deployment, the system variables are automatically replaced with the actual value. This implements multi-environment use with one-time configuration through file mounting.

System Variables of a Configuration File

For details about the system variables that can be written into a configuration file, see Table 1.

**Table 1** System variables
Variable Name	Description
PAAS_PROJECT_ID	Project ID.
CAS_ENVIRONMENT_ID	Environment ID.
CAS_ENVIRONMENT_NAME	Environment name.
CAS_APPLICATION_ID	Application ID.
CAS_APPLICATION_NAME	Application name.
CAS_COMPONENT_ID	Component ID.
CAS_INSTANCE_ID	Component instance ID.
CAS_INSTANCE_NAME	Component instance name.
CAS_INSTANCE_VERSION	Component instance version.
PAAS_PROJECT_NAME	Project name.
AOM_DISCOVERY_RULE_VERSION	AOM discovery rule name.
PAAS_REGION_NAME	Region name.
PAAS_CSE_CC_ENDPOINT	CSE configuration center address.
PAAS_CSE_SC_ENDPOINT	CSE registry center address.
DISTRIBUTED_CACHE_PASSWORD	Distributed cache password.
DISTRIBUTED_CACHE_TYPE	Distributed cache type.
DISTRIBUTED_CACHE_PORT	Distributed cache port.
DISTRIBUTED_CACHE_HOST	Distributed cache address.
DISTRIBUTED_CACHE_VERSION	Distributed cache version.
DISTRIBUTED_CACHE_CLUSTER	Distributed cache cluster type.
RELATIONAL_DATABASE_PASSWORD	Cloud database password.
RELATIONAL_DATABASE_DB_TYPE	Cloud database type.
RELATIONAL_DATABASE_JNDI_NAME	Cloud database JNDI name.
RELATIONAL_DATABASE_HOST	Cloud database address.
RELATIONAL_DATABASE_CONNECTION_TYPE	Cloud database connection type.
RELATIONAL_DATABASE_DB_NAME	Cloud database name.
RELATIONAL_DATABASE_DB_USER	Cloud database account.
RELATIONAL_DATABASE_PORT	Cloud database port.
RELATIONAL_DATABASE_NAME	Cloud database name.
RELATIONAL_DATABASE_VERSION	Cloud database version.