etcd operator degraded with 'EtcdMembersAvailable: 2 of 3 members are available, master-0 is unhealthy'

Issue

• ETCD operator went into the degraded state withEtcdMembersAvailable: 2 of 3 members are available, master-0 is unhealthy

• All etcd pods are running

NAME                        READY  STATUS     RESTARTS  
etcd-master-0               4/4    Running    0         
etcd-master-1               4/4    Running    0         
etcd-master-2               4/4    Running    0        

• The etcd peer address and the master node IP address is different.

$ oc get nodes 

NAME            STATUS  ROLES   AGE  VERSION          INTERNAL-IP    
master-0        Ready   master  22d  v1.18.3+6c42de8  10.X.YYY.154       
master-1        Ready   master  22d  v1.18.3+6c42de8  10.X.YYY.168         
master-2        Ready   master  22d  v1.18.3+6c42de8  10.X.YYY.169       

sh-4.2# etcdctl member list -w table
+------------------+---------+--------------------+---------------------------+---------------------------+------------+
|        ID        | STATUS  |        NAME        |        PEER ADDRS         |       CLIENT ADDRS        | IS LEARNER |
+------------------+---------+--------------------+---------------------------+---------------------------+------------+
| 846f200b000823e4 | started | master-2           | https://10.X.YYY.169:2380 | https://10.X.YYY.169:2379 |      false |
| e440a30b0868805b | started | master-0           | https://10.X.YYY.150:2380 | https://10.X.YYY.150:2379 |      false |
| fa52630838cad1ab | started | master-1           | https://10.X.YYY.168:2380 | https://10.X.YYY.168:2379 |      false |
+------------------+---------+--------------------+---------------------------+---------------------------+------------+