What's Actually Happening
etcd cluster reports unhealthy status. Kubernetes control plane may be affected as etcd is the backing store.
The Error You'll See
```bash $ etcdctl endpoint health
http://10.0.0.1:2379 is unhealthy: failed to commit proposal: context deadline exceeded ```
Why This Happens
- 1.Member down
- 2.Quorum loss
- 3.Network partition
- 4.Disk issues
- 5.Clock skew
Step 1: Check Cluster Health
etcdctl endpoint health --cluster
etcdctl endpoint status --cluster -w tableStep 2: Check Member List
etcdctl member list -w tableStep 3: Check Logs
journalctl -u etcd -fStep 4: Check Network
nc -zv etcd-1 2379
nc -zv etcd-1 2380Step 5: Check Disk
df -h /var/lib/etcd
iostat -x 1 5Step 6: Check Quorum
# Must have majority (N/2 + 1) members up
# For 3-node cluster: need 2 members
# For 5-node cluster: need 3 membersStep 7: Restart Member
systemctl restart etcdStep 8: Remove Failed Member
etcdctl member remove <member-id>Step 9: Add New Member
etcdctl member add etcd-new --peer-urls=http://10.0.0.4:2380Step 10: Defragment
etcdctl defrag
etcdctl compact <revision>Related Issues
- [Fix etcd Leader Election Failed](/articles/fix-etcd-leader-election-failed)
- [Fix Kubernetes API Server Not Responding](/articles/fix-kubernetes-api-server-not-responding)