title: Docker container mac address change
body: <p>I have an application that uses a MAC Address for licensing. I'd like to run this application in a docker container for CI/CD purposes. I created a docker container and use the <code>ENTRYPOINT</code> to run a shell script. The issue I am running into now is that when I try to ping any server I get network errors. I am wondering if this is something that I can fix or if I am doing this incorrectly. I'd love to find a solution for this so I can test scripts that I write for this system before pushing them to production. I'll be around to answer any additional questions.</p>
  <p><strong>Dockerfile</strong></p>
  <pre><code>FROM centos:latest
  COPY startup.sh /startup.sh
  ENTRYPOINT [&quot;/bin/sh&quot;, &quot;/startup.sh&quot;]
  </code></pre>
  <p><strong>startup.sh</strong></p>
  <pre><code>ip link set dev eth0 down;
  ip link set dev eth0 address 02:42:ac:11:00:11;
  ip link set dev eth0 up;
  </code></pre>
  <p><strong>Errors</strong></p>
  <pre><code>sh-4.4# ip link
  1: lo: &lt;LOOPBACK,UP,LOWER_UP&gt; mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
      link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  2: sit0@NONE: &lt;NOARP&gt; mtu 1480 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/sit 0.0.0.0 brd 0.0.0.0
  29: eth0@if30: &lt;BROADCAST,MULTICAST,UP,LOWER_UP&gt; mtu 1500 qdisc noqueue state UP mode DEFAULT group default
      link/ether 02:42:ac:11:00:11 brd ff:ff:ff:ff:ff:ff link-netnsid 0
  
  sh-4.4# ping google.com
  ping: google.com: Name or service not known
  
  sh-4.4# ping 4.4.4.4
  connect: Network is unreachable
  </code></pre>