<p dir="auto"><strong>Is this a request for help?</strong> (If yes, you should use our troubleshooting guide and community support channels, see <a href="http://kubernetes.io/docs/troubleshooting/" rel="nofollow">http://kubernetes.io/docs/troubleshooting/</a>.):</p>
<p dir="auto">No</p>
<p dir="auto"><strong>What keywords did you search in Kubernetes issues before filing this one?</strong> (If you have found any duplicates, you should instead reply there.):</p>
<p dir="auto">controller key, duplicate certificates, controller rekey</p>
<hr>
<p dir="auto"><strong>Is this a BUG REPORT or FEATURE REQUEST?</strong> (choose one):</p>
<p dir="auto">bug report</p>

<p dir="auto"><strong>Kubernetes version</strong> (use <code class="notranslate">kubectl version</code>):</p>
<p dir="auto">Client Version: version.Info{Major:"1", Minor:"4", GitVersion:"v1.4.3", GitCommit:"4957b090e9a4f6a68b4a40375408fdc74a212260", GitTreeState:"clean", BuildDate:"2016-10-16T06:36:33Z", GoVersion:"go1.6.3", Compiler:"gc", Platform:"linux/amd64"}<br>
Server Version: version.Info{Major:"1", Minor:"4", GitVersion:"v1.4.3", GitCommit:"4957b090e9a4f6a68b4a40375408fdc74a212260", GitTreeState:"clean", BuildDate:"2016-10-16T06:20:04Z", GoVersion:"go1.6.3", Compiler:"gc", Platform:"linux/amd64"}</p>
<p dir="auto"><strong>Environment</strong>:</p>
<ul dir="auto">
<li><strong>Cloud provider or hardware configuration</strong>: self-hosted VM</li>
<li><strong>OS</strong> (e.g. from /etc/os-release): Ubuntu 14.04.05</li>
<li><strong>Kernel</strong> (e.g. <code class="notranslate">uname -a</code>): 4.4.0-45</li>
<li><strong>Install tools</strong>: Manual installation</li>
<li><strong>Others</strong>:</li>
</ul>
<p dir="auto"><strong>What happened</strong>:</p>
<p dir="auto">I generated an independent cert+key for each of my two controllers. Pods (especially kube-dns) had a high failure rate in talking to the apiserver. This showed up as 401 status in the apiserver log, and "the server requested the client to provide authenticate" in the pod kubedns log.</p>
<p dir="auto"><strong>What you expected to happen</strong>:</p>
<p dir="auto">I expected it to work. :)</p>
<p dir="auto"><strong>How to reproduce it</strong> (as minimally and precisely as possible):</p>
<ol dir="auto">
<li>Generate a different certificate and key for each controller machine (apiserver, controller manager, scheduler).</li>
<li>Load kube-dns.</li>
</ol>
<p dir="auto"><strong>Anything else do we need to know</strong>:</p>
<p dir="auto">In many places, standard practice is to issue an independent certificate for each server. If Kubernetes doesn't support that configuration, it should be documented.</p>
<p dir="auto"><strong>Is this a request for help?</strong> (If yes, you should use our troubleshooting guide and community support channels, see <a href="http://kubernetes.io/docs/troubleshooting/" rel="nofollow">http://kubernetes.io/docs/troubleshooting/</a>.): No</p>
<p dir="auto"><strong>What keywords did you search in Kubernetes issues before filing this one?</strong> (If you have found any duplicates, you should instead reply there.):</p>
<p dir="auto">Unable to use a TTY</p>
<hr>
<p dir="auto"><strong>Is this a BUG REPORT or FEATURE REQUEST?</strong> (choose one):</p>
<p dir="auto">BUG REPORT</p>

<p dir="auto"><strong>Kubernetes version</strong> (use <code class="notranslate">kubectl version</code>):<br>
root@kube-master:<del># kubectl version<br>
Client Version: version.Info{Major:"1", Minor:"4+", GitVersion:"v1.4.7-beta.0.2+1ef121737093fd-dirty", GitCommit:"1ef121737093fdefada11034782d235a205f567f", GitTreeState:"dirty", BuildDate:"2016-11-25T03:02:28Z", GoVersion:"go1.7.3 ibm-1.7", Compiler:"gc", Platform:"linux/ppc64le"}<br>
Server Version: version.Info{Major:"1", Minor:"4+", GitVersion:"v1.4.7-beta.0.2+1ef121737093fd-dirty", GitCommit:"1ef121737093fdefada11034782d235a205f567f", GitTreeState:"dirty", BuildDate:"2016-11-25T03:02:28Z", GoVersion:"go1.7.3 ibm-1.7", Compiler:"gc", Platform:"linux/ppc64le"}<br>
root@kube-master:</del>#</p>
<p dir="auto"><strong>Environment</strong>:</p>
<ul dir="auto">
<li><strong>Cloud provider or hardware configuration</strong>: hardware configuration</li>
<li><strong>OS</strong> (e.g. from /etc/os-release):</li>
</ul>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="NAME=&quot;Ubuntu&quot;
VERSION=&quot;16.04.1 LTS (Xenial Xerus)&quot;
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME=&quot;Ubuntu 16.04.1 LTS&quot;
VERSION_ID=&quot;16.04&quot;
HOME_URL=&quot;http://www.ubuntu.com/&quot;
SUPPORT_URL=&quot;http://help.ubuntu.com/&quot;
BUG_REPORT_URL=&quot;http://bugs.launchpad.net/ubuntu/&quot;
UBUNTU_CODENAME=xenial"><pre class="notranslate"><code class="notranslate">NAME="Ubuntu"
VERSION="16.04.1 LTS (Xenial Xerus)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 16.04.1 LTS"
VERSION_ID="16.04"
HOME_URL="http://www.ubuntu.com/"
SUPPORT_URL="http://help.ubuntu.com/"
BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/"
UBUNTU_CODENAME=xenial
</code></pre></div>
<ul dir="auto">
<li><strong>Kernel</strong> (e.g. <code class="notranslate">uname -a</code>):  Linux kube-master 4.4.0-47-generic <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="35537532" data-permission-text="Title is private" data-url="https://github.com/kubernetes/kubernetes/issues/68" data-hovercard-type="pull_request" data-hovercard-url="/kubernetes/kubernetes/pull/68/hovercard" href="https://github.com/kubernetes/kubernetes/pull/68">#68</a>-Ubuntu SMP Wed Oct 26 19:38:24 UTC 2016 ppc64le ppc64le ppc64le GNU/Linux</li>
<li><strong>Install tools</strong>:</li>
<li><strong>Others</strong>:</li>
</ul>
<p dir="auto"><strong>What happened</strong>:</p>
<p dir="auto">kubectl exec -it &lt;pod_name&gt; -- /bin/bash fails with error  "Unable to use a TTY" and never get a prompt</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="root@kube-master:~# kubectl exec -it my-nginx-2833891535-ycsq2 -- /bin/bash
Unable to use a TTY - input is not a terminal or the right kind of file

=============&gt; never get a prompt"><pre class="notranslate"><code class="notranslate">root@kube-master:~# kubectl exec -it my-nginx-2833891535-ycsq2 -- /bin/bash
Unable to use a TTY - input is not a terminal or the right kind of file

=============&gt; never get a prompt
</code></pre></div>
<p dir="auto"><strong>What you expected to happen</strong>:</p>
<p dir="auto">Could use kubectl exec -it &lt;pod_name&gt; -- /bin/bash to get the shell prompt of the POD.</p>
<p dir="auto"><strong>How to reproduce it</strong> (as minimally and precisely as possible):</p>
<ol dir="auto">
<li>Install Kubernetes 1.4.7</li>
<li>Deploy an application</li>
<li>Run kuectl exec -it &lt;pod_name&gt; -- /bin/bash</li>
</ol>
<p dir="auto"><strong>Anything else do we need to know</strong>:</p>
<p dir="auto">I could use docker exec -it &lt;container_name&gt; /bin/bash to get the prompt, but kubectl exec does not work.</p>