Storage is the durability boundary used by the rule engine, certificate cache, and signing CA. v1 provides POSIX and S3 implementations with the same keyspace:

Key Content
ca.p12 signing CA, strongly encrypted under clusterKey
certs/... cached public certificate/chain material; no leaf private keys
rules/default complete source-address fallback table
rules/ip/... per-source-address rule overrides

Use POSIX for one node and S3 for a fleet. Telemetry spools are deliberately outside Storage and rotate independently on each node.

See Storage backends and Secrets at rest.