<p>I set up the <code>kubernetes</code> cluster, and I found the <code>pause-amd64:3.0</code> container on master or minion like this:</p>

<pre><code>[root@k8s-minion1 kubernetes]# docker ps |grep pause
c3026adee957        gcr.io/google_containers/pause-amd64:3.0           "/pause"                 22 minutes ago      Up 22 minutes                           k8s_POD.d8dbe16c_redis-master-343230949-04glm_default_ce3f60a9-095d-11e7-914b-0a77ecd65f3e_66c108d5
202df18d636e        gcr.io/google_containers/pause-amd64:3.0           "/pause"                 24 hours ago        Up 24 hours                             k8s_POD.d8dbe16c_kube-proxy-js0z0_kube-system_2866cfc2-0891-11e7-914b-0a77ecd65f3e_c8e1a667
072d3414d33a        gcr.io/google_containers/pause-amd64:3.0           "/pause"                 24 hours ago        Up 24 hours                             k8s_POD.d8dbe16c_kube-flannel-ds-tsps5_default_2866e3fb-0891-11e7-914b-0a77ecd65f3e_be4b719e
[root@k8s-minion1 kubernetes]#
</code></pre>

<p>so what does <code>k8s</code> use this for ? </p>

<p>It's part of the infrastructure. This container is started first in all Pods to setup the network for the Pod.</p>

<p>It does nothing after the Pod has started.</p>

<p>Here is the <a href="https://github.com/kubernetes/kubernetes/tree/master/build/pause" rel="noreferrer">source code</a>.</p>
