<p>I am running K8S cluster on-premise (Nothing in the cloud) with one K8S Master and two worker nodes.</p>
<ul>
<li>k8s-master : 192.168.100.100</li>
<li>worker-node-1 : 192.168.100.101</li>
<li>worker-node-2 : 192.168.100.102</li>
</ul>
<p>I used kubernetes / ingress-nginx for routing traffic to my simple App.
These are my pods running on both workers nodes:</p>
<pre><code>[root@k8s-master ingress]# kubectl get pods -A -o wide
NAMESPACE              NAME                                         READY   STATUS    RESTARTS   AGE   IP                NODE            NOMINATED NODE   READINESS GATES
default                hello-685445b9db-b7nql                       1/1     Running   0          44m   10.5.2.7          worker-node-2   &lt;none&gt;           &lt;none&gt;
default                hello-685445b9db-ckndn                       1/1     Running   0          44m   10.5.2.6          worker-node-2   &lt;none&gt;           &lt;none&gt;
default                hello-685445b9db-vd6h2                       1/1     Running   0          44m   10.5.1.18         worker-node-1   &lt;none&gt;           &lt;none&gt;
default                ingress-nginx-controller-56c75d774d-p7whv    1/1     Running   1          30h   10.5.1.14         worker-node-1   &lt;none&gt;           &lt;none&gt;
kube-system            coredns-74ff55c5b-s8zss                      1/1     Running   12         16d   10.5.0.27         k8s-master      &lt;none&gt;           &lt;none&gt;
kube-system            coredns-74ff55c5b-w6rsh                      1/1     Running   12         16d   10.5.0.26         k8s-master      &lt;none&gt;           &lt;none&gt;
kube-system            etcd-k8s-master                              1/1     Running   12         16d   192.168.100.100   k8s-master      &lt;none&gt;           &lt;none&gt;
kube-system            kube-apiserver-k8s-master                    1/1     Running   12         16d   192.168.100.100   k8s-master      &lt;none&gt;           &lt;none&gt;
kube-system            kube-controller-manager-k8s-master           1/1     Running   14         16d   192.168.100.100   k8s-master      &lt;none&gt;           &lt;none&gt;
kube-system            kube-flannel-ds-76mt8                        1/1     Running   1          30h   192.168.100.102   worker-node-2   &lt;none&gt;           &lt;none&gt;
kube-system            kube-flannel-ds-bfnjw                        1/1     Running   10         16d   192.168.100.101   worker-node-1   &lt;none&gt;           &lt;none&gt;
kube-system            kube-flannel-ds-krgzg                        1/1     Running   13         16d   192.168.100.100   k8s-master      &lt;none&gt;           &lt;none&gt;
kube-system            kube-proxy-6bq6n                             1/1     Running   1          30h   192.168.100.102   worker-node-2   &lt;none&gt;           &lt;none&gt;
kube-system            kube-proxy-df8fn                             1/1     Running   13         16d   192.168.100.100   k8s-master      &lt;none&gt;           &lt;none&gt;
kube-system            kube-proxy-z8q2z                             1/1     Running   10         16d   192.168.100.101   worker-node-1   &lt;none&gt;           &lt;none&gt;
kube-system            kube-scheduler-k8s-master                    1/1     Running   12         16d   192.168.100.100   k8s-master      &lt;none&gt;           &lt;none&gt;
kubernetes-dashboard   dashboard-metrics-scraper-799cd98cf6-zh8xs   1/1     Running   9          16d   192.168.100.101   worker-node-1   &lt;none&gt;           &lt;none&gt;
kubernetes-dashboard   kubernetes-dashboard-74d688b6bc-hvxgm        1/1     Running   10         16d   10.5.1.17         worker-node-1   &lt;none&gt;           &lt;none&gt;
</code></pre>
<p>And these are the services running on my cluster:</p>
<pre><code>[root@k8s-master ingress]# kubectl get svc
NAME                                 TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)                      AGE
hello                                NodePort    10.105.236.241   &lt;none&gt;        80:31999/TCP                 30h
ingress-nginx-controller             NodePort    10.110.141.41    &lt;none&gt;        80:30428/TCP,443:32682/TCP   30h
ingress-nginx-controller-admission   ClusterIP   10.109.15.31     &lt;none&gt;        443/TCP                      30h
kubernetes                           ClusterIP   10.96.0.1        &lt;none&gt;        443/TCP                      16d
</code></pre>
<p>And this is the ingress description:</p>
<pre><code>[root@k8s-master ingress]# kubectl describe  ingress ingress-hello
Name:             ingress-hello
Namespace:        default
Address:          10.110.141.41
Default backend:  default-http-backend:80 (&lt;error: endpoints &quot;default-http-backend&quot; not found&gt;)
Rules:
  Host        Path  Backends
  ----        ----  --------
  *
              /hello   hello:80 (10.5.1.18:80,10.5.2.6:80,10.5.2.7:80)
Annotations:  kubernetes.io/ingress.class: nginx
              nginx.ingress.kubernetes.io/rewrite-target: /
</code></pre>
<p>The issue is when accessing the first node by visiting worker-node-1 IP Address with Ingress Controller Port = <strong>30428</strong>, <strong><a href="http://192.168.100.101:30428" rel="nofollow noreferrer">http://192.168.100.101:30428</a></strong>, its working fine with no problems.
While accessing worker-node-2 by visiting IP with same ingress port <strong>30428</strong>, its <strong>NOT RESPONDING</strong> from out side the node and also from inside the node too by accessing the URL: <strong><a href="http://192.168.100.102:30428" rel="nofollow noreferrer">http://192.168.100.102:30428</a></strong> .
I also tried executing telnet command (inside the worker node 2), no luck also:</p>
<pre><code>[root@worker-node-2 ~]# telnet 192.168.100.102 30428
Trying 192.168.100.102...
</code></pre>
<p>The most interesting thing is the port is shows up in netstat command, as I am executing this command from inside the Node-2 , showing ingress Port:30428 is in <strong>LISTEN</strong> state:</p>
<pre><code>[root@worker-node-2 ~]# netstat -tulnp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 127.0.0.1:10248         0.0.0.0:*               LISTEN      1284/kubelet
tcp        0      0 127.0.0.1:10249         0.0.0.0:*               LISTEN      2578/kube-proxy
tcp        0      0 0.0.0.0:32682           0.0.0.0:*               LISTEN      2578/kube-proxy
tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN      1/systemd
tcp        0      0 192.168.122.1:53        0.0.0.0:*               LISTEN      1856/dnsmasq
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1020/sshd
tcp        0      0 127.0.0.1:631           0.0.0.0:*               LISTEN      1016/cupsd
tcp        0      0 127.0.0.1:41561         0.0.0.0:*               LISTEN      1284/kubelet
tcp        0      0 0.0.0.0:30428           0.0.0.0:*               LISTEN      2578/kube-proxy
tcp        0      0 0.0.0.0:31999           0.0.0.0:*               LISTEN      2578/kube-proxy
tcp6       0      0 :::10250                :::*                    LISTEN      1284/kubelet
tcp6       0      0 :::111                  :::*                    LISTEN      1/systemd
tcp6       0      0 :::10256                :::*                    LISTEN      2578/kube-proxy
tcp6       0      0 :::22                   :::*                    LISTEN      1020/sshd
tcp6       0      0 ::1:631                 :::*                    LISTEN      1016/cupsd
udp        0      0 0.0.0.0:5353            0.0.0.0:*                           929/avahi-daemon: r
udp        0      0 0.0.0.0:44997           0.0.0.0:*                           929/avahi-daemon: r
udp        0      0 192.168.122.1:53        0.0.0.0:*                           1856/dnsmasq
udp        0      0 0.0.0.0:67              0.0.0.0:*                           1856/dnsmasq
udp        0      0 0.0.0.0:111             0.0.0.0:*                           1/systemd
</code></pre>
<p>based on my understanding , all worker node must expose NodePort for &quot;ingress controller&quot; port which=30428??</p>
<p><strong>Edited:</strong>
I found that <strong>&quot;ingress-nginx-controller-56c75d774d-p7whv&quot;</strong> is deployed only on node-1.
Do I need to make sure that the ingress-nginx controller is running on all nodes? how to achieve that if this statement is true?</p>

Faris Rjoub
<p>Kubernetes networking (kube-proxy to be more specific) uses iptables to control the network connections between pods and nodes. Since Centos 8 uses <code>nftables</code> instead  <code>iptables</code> this cause networking issues.</p>
<p>Calico in v.3.8.1+ included support for hosts which uses iptables in NFT mode.
The solution is to set <code>FELIX_IPTABLESBACKEND=NFT</code> option. This will tell Calico to use nftables backed.</p>
<blockquote>
<p>This parameter controls which variant of iptables binary Felix uses.
Set this to <code>Auto</code> for auto detection of the backend. If a specific
backend is needed then use <code>NFT</code> for hosts using a netfilter backend
or <code>Legacy</code> for others. [Default: <code>Legacy</code>]</p>
</blockquote>
<p>Please visit this calico page to check how to <a href="https://docs.projectcalico.org/reference/felix/configuration" rel="nofollow noreferrer">configure felix</a>.
For more reading please visit <a href="https://github.com/projectcalico/calico/issues/2322#issuecomment-515239775" rel="nofollow noreferrer">this github issues</a>.</p>
