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- manually by the site operator
- automatically via PROM, based on healthiness of active site
Manual (forced) failover
The manual option would be utilized by site operators wishing to force activity to a particular site so that they may proceed with performing maintenance or other activities on the other site without impacting service. Prior to carrying out this activity, it is suggested that the current role of the site(s) be determined (see SDN-C Site Role Detection).
From the Kubernetes master node in the site, simply run the makeActive script:
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The PROM instance in each SDN-C site is responsible for monitoring periodically ascertaining the health of the local site as well as the role of the site so that it may decide whether or not the local site should be made the active sitebased on the health of each component. This information is published to MUSIC in order for the remote site to also be aware of this information.
If the local PROM instance determines that the site is currently 'standby' and the remote site has become unhealthy, it will proceed to automatically initiate failover procedures, making the local site 'active' while the remote site is reverted to 'standby'.
The following script can be used to switch between the primary and secondary roles for an SDNC server.
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