<p>I am a programmer trying to get Rancher (Kubernetes) setup.  Rancher's config file has a setting called <code>service_cluster_ip_range</code>.  </p>

<p>It expects a CIDR notated subnet.</p>

<p>My network team gave me a "24" subnet.  They told me that the IP address range I can use is 10.70.9.11 - 10.70.9.254.</p>

<p>As I understand things, when you say 10.70.9.0/24 you are referring to 10.70.9.1 - 10.70.9.254.</p>

<p>When I asked my network team if I could have addresses 1 - 10 as well I was told that they were reserved for network gear (and that the network would fail if they gave me those addresses).</p>

<p>So, my question is does CIDR deal with exclusions like this?  <strong>Can you say something like <code>10.70.9.0/24 Exluding (.1 through .10)</code> or something like that?</strong></p>

<p>Or will have have to give up a bunch of addresses and do 10.80.9.128/25?</p>

<p>You cannot express exclusions with CIDR notation. You can give up bunch of IP addresses by using /25 range. </p>
