_default_asg.html.md.erb

Elastic Runtime defines one default ASG, `default_security_group`. 
This group allows all outbound traffic from application containers on public and private networks except for the link-local range, `169.254.0.0/16`, which is blocked.

<p class="note warning"><strong>WARNING</strong>: For security, Elastic Runtime administrators must <a href="../opsguide/app-sec-groups.html">modify the default ASGs</a> so that outbound network traffic cannot access internal components.</p>

The ASG is defined in the Cloud Controller configuration as follows:

<pre>
security_group_definitions:
- name: default_security_group
  rules:
  - protocol: all
    destination: 0.0.0.0-169.253.255.255
  - protocol: all
    destination: 169.255.0.0-255.255.255.255
</pre>