<p>In a multi-master kubernetes cluster, do only one master schedule and are the other masters in a standby mode? Does all the masters coordinate and schedule pods and etc?</p>

jarge
<p>That's mostly correct; one can see that process by looking at the logs of all the <code>controller-manager</code> Pods and observing:</p>
<blockquote>
<p>I1021 00:09:49.283273       1 leaderelection.go:243] attempting to acquire leader lease  kube-system/kube-controller-manager...</p>
</blockquote>
<p>in some of them, and more &quot;working&quot; messages in just one of them:</p>
<blockquote>
<p>I1021 02:12:51.779698       1 cleaner.go:181] Cleaning CSR &quot;csr-rf8vh&quot; as it is more than 1h0m0s old and approved.</p>
</blockquote>
<p>I say &quot;mostly correct&quot; because to the best of my knowledge all <code>apiserver</code> Pods are actively doing work -- or at the very least they service HTTPS traffic and emit Audit logs -- but the rest of the HA components use that leader lease pattern</p>
<p>As for your 2nd question</p>
<blockquote>
<p>Does all the masters coordinate and schedule pods and etc?</p>
</blockquote>
<p>no, that's the job of the <code>scheduler</code> Pods, which, again, use that leader lease pattern in order to avoid competing scheduling decisions</p>
