Update csi-debug.md

Author: andyzhangx

docs/csi-debug.md

@@ -1,18 +1,19 @@
 ## CSI driver debug tips
 
 ### case#1: volume create/delete failed
- - locate csi driver pod
+> There could be multiple controller pods (only one pod is the leader), if there are no helpful logs, try to get logs from the leader controller pod.
+ - find csi driver controller pod
 ```console
 $ kubectl get pod -o wide -n kube-system | grep csi-nfs-controller
 NAME                                     READY   STATUS    RESTARTS   AGE     IP             NODE
 csi-nfs-controller-56bfddd689-dh5tk      5/5     Running   0          35s     10.240.0.19    k8s-agentpool-22533604-0
 csi-nfs-controller-56bfddd689-sl4ll      5/5     Running   0          35s     10.240.0.23    k8s-agentpool-22533604-1
 ```
- - get csi driver logs
+ - get pod description and logs
 ```console
+$ kubectl describe csi-nfs-controller-56bfddd689-dh5tk -n kube-system > csi-nfs-controller-description.log
 $ kubectl logs csi-nfs-controller-56bfddd689-dh5tk -c nfs -n kube-system > csi-nfs-controller.log
 ```
-> note: there could be multiple controller pods, if there are no helpful logs, try to get logs from other controller pods
 
 ### case#2: volume mount/unmount failed
  - locate csi driver pod that does the actual volume mount/unmount
@@ -24,8 +25,9 @@ csi-nfs-node-cvgbs                        3/3     Running   0          7m4s    1
 csi-nfs-node-dr4s4                        3/3     Running   0          7m4s    10.240.0.4     k8s-agentpool-22533604-0
 ```
 
- - get csi driver logs
+ - get pod description and logs
 ```console
+$ kubectl describe po csi-nfs-node-cvgbs -n kube-system > csi-nfs-node-description.log
 $ kubectl logs csi-nfs-node-cvgbs -c nfs -n kube-system > csi-nfs-node.log
 ```