The Author Online Book Forums are Moving

The Author Online Book Forums will soon redirect to Manning's liveBook and liveVideo. All book forum content will migrate to liveBook's discussion forum and all video forum content will migrate to liveVideo. Log in to liveBook or liveVideo with your Manning credentials to join the discussion!

Thank you for your engagement in the AoF over the years! We look forward to offering you a more enhanced forum experience.

270922 (3) [Avatar] Offline
#1
Under topic "ENSURING HIGH AVAILABILITY OF THE CONTROLLERS AND THE SCHEDULER" it is said:
"The Controller Manager and Scheduler can run collocated with the API server and etcd, or they
can run on separate machines. When collocated, they can talk to the local API server directly,
otherwise they connect to the API servers through the load balancer."

If Controller Manager and Scheduler talks to the local API server, isn't there a risk of system halting if the local API server goes down?
Marko Lukša (70) [Avatar] Offline
#2
No. Let's say the Controller Manager running on master A is the active Controller Manager in the cluster (it was elected as the leader). If the API server on master A dies, the Controller Manager will no longer be able to update the resource that designates who the leader is. This will allow another Controller Manager on a different master node to take the leader position.