Configuring high availability in Teracloud® Streams enterprise domains

If you configure high availability for the management services in a domain, Teracloud® Streams can switch to using standby services in the event of a software, hardware, or network interruption.

Before you begin

For high availability with automatic recovery from failures, the domain controller service must be running as a Linux™ system service on the Teracloud® Streams resource. For more information, see Options for setting up the domain controller service on Teracloud® Streams resources.

About this task

To configure high availability for a domain, set the domain.highAvailabilityCount domain property to a value greater than one. This property specifies the total number of each Teracloud® Streams domain management service. For example, a value of three means that there is one active and two standby services for each management service in the domain. Teracloud® Streams can switch to using standby services in the event of a software, hardware, or network interruption. For more information about this domain property, run streamtool man domainproperties.
Note: The web management service is not affected by the domain.highAvailabilityCount setting because that service does not have any standby services. The web management service can run on resources that are tagged as sws or management resources.
To affect the placement of active and standby services on the resources in your domain, tag the resources. For example, management services for the domain run on resources that have the following management tag. If you prefer to run specific management services on specific resources, use the appropriate tags for those services. For example, the authentication and authorization service runs on resources that have the following authentication tag.
Note: There can be only one JMX management API service for each resource. The standby services for the JMX management API service can run on other resources that are tagged as jmx or management resources.
Note: There can be only one REST management API service for each resource. The standby services for the REST management API service can run on other resources that are tagged as rest or management resources.
For more information about the Teracloud® Streams services and tags, see Domain and instance services.

Procedure

  • To change the domain.highAvailabilityCount domain property value, use the streamtool setdomainproperty command.
    You can also specify that property value when you create the domain.
  • To change the tags that are associated with resources, use the Streams Console or the streamtool chhost command.
    For more information, see Assigning tags to resources in a domain.