Question 17
Domain 2: Cluster HardeningWhy is etcd backup preparation relevant before certain cluster upgrade operations?
Correct answer: A
Explanation
etcd is the cluster’s source of truth for control-plane state, so an upgrade can affect the data needed to manage the cluster. Having recoverable backups means the state can be restored if an upgrade or misstep corrupts it, preventing loss of cluster configuration and availability.
Why each option is right or wrong
A. etcd stores cluster state, so recoverable backups help if an upgrade or misstep corrupts control-plane state
Kubernetes control-plane state is persisted in etcd, and the official etcd disaster-recovery guidance requires taking a consistent snapshot before disruptive maintenance because an upgrade can leave the datastore unreadable or inconsistent. In practice, a backup is the only way to restore the cluster’s state if the control plane is damaged during the operation, since kube-apiserver depends on etcd for all persisted configuration and object data.
B. etcd backups increase Pod startup speed
Pod startup speed depends on scheduling, image pulls, and node readiness, not etcd backup existence.
C. RBAC cannot work unless etcd is backed up hourly
RBAC data is stored in cluster state, but RBAC does not require hourly backups to function.
D. etcd is only used for logs, so backup size stays trivial
etcd stores Kubernetes state and metadata, not just logs, so its role is far broader.