<p>At first, I set limit range for namespace <code>kube-system</code> as below:</p>
<pre><code>apiVersion: v1
kind: LimitRange
metadata:
  name: cpu-limit-range
  namespace: kube-system
spec:
  limits:
  - default:
      cpu: 500m
      memory: 500Mi
    defaultRequest:
      cpu: 100m
      memory: 100Mi
    type: Container
</code></pre>
<p>However, later found that there is insufficient CPU and Memory to start up my pod as limits are &gt; 100% from namespace <code>kube-system</code> already.</p>
<p>How can I reset reasonable limits for pods in <code>kube-system</code>. It is better to set their limits to <code>unlimitted</code> but I don't know how to set it.</p>
<hr />
<p>Supplement information for namespace <code>kube-system</code>:</p>
<p><a href="https://i.stack.imgur.com/cU72x.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cU72x.png" alt="enter image description here" /></a></p>

DaiKeung
<p>Not sure if your <code>kube-system</code> namespace has a limit set. You can confirm it checking the namespace itself:</p>
<pre><code>kubectl describe namespace kube-system
</code></pre>
<p>If you have a limit range or a resource quota set, it will appear in the description. Something like the following:</p>
<pre><code>Name:         default-cpu-example
Labels:       &lt;none&gt;
Annotations:  &lt;none&gt;
Status:       Active

No resource quota.

Resource Limits
 Type       Resource  Min  Max  Default Request  Default Limit  Max Limit/Request Ratio
 ----       --------  ---  ---  ---------------  -------------  -----------------------
 Container  cpu       -    -    500m             1              -
</code></pre>
<p>In this case I have set resource limits for my namespace.</p>
<p>Now I can list all the ResourceQuotas and LimitRanges using:</p>
<pre><code>kubectl get resourcequotas -n kube-system
kubectl get limitranges -n kube-system
</code></pre>
<p>If somethings returns, from those you can simply remove it:</p>
<pre><code>kubectl delete resourcequotas NAME_OF_YOUR_RESOURCE_QUOTA -n kube-system
kubectl delete limitranges NAME_OF_YOUR_LIMIT_RANGE -n kube-system
</code></pre>
<p>I'm still not sure if that's your true problem, but that answers your question.</p>
<p>You can find more info here:</p>
<p><a href="https://kubernetes.io/docs/tasks/administer-cluster/manage-resources/cpu-default-namespace/" rel="nofollow noreferrer">https://kubernetes.io/docs/tasks/administer-cluster/manage-resources/cpu-default-namespace/</a></p>
