My pods are staying in Pending state, as all the answers mentioned I tried to get describe output but no idea about why it is staying in Pending state:
k8s@k8s-master:~/deployment$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master Ready master 12d v1.12.2
k8s-node-1 Ready <none> 12d v1.12.2
k8s-node-2 Ready <none> 12d v1.12.2
k8s@k8s-master:~/deployment$ kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx 0/1 Pending 0 62m
webserver 0/1 Pending 0 13m
k8s@k8s-master:~/deployment$ kubectl describe pod webserver
Name: webserver
Namespace: default
Priority: 0
PriorityClassName: <none>
Node: <none>
Labels: creator=rithin
Annotations: <none>
Status: Pending
IP:
Containers:
apache:
Image: httpd
Port: <none>
Host Port: <none>
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-vdpls (ro)
Volumes:
default-token-vdpls:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-vdpls
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events: <none>Already tried describing the pods, but no info
Your pods require manual scheduling. In your yaml file for the pods add nodeName: k8s-master at the same level of containers under spec.
Your pods would be scheduled at the k8s-master node. If you want to schedule it in any other node, replace "k8s-master" with the appripriate node name.
Well I couldn't find any logs related to failure. So recreated the cluster and now it is working. I assume it was a problem with flannel.
One possiblity is that worker node is not reachable from master node as there is no node assigned to the pod.