NOTE
ZooKeeper Znode Properties
Persistent, ephemeral, sequential nodes; versions; ACLs; session ownership; and coordination semantics.
This is a historical learning note and may contain outdated or incomplete understanding.
ZooKeeper znodes can be persistent or session-bound ephemeral nodes and can optionally use sequential naming. Sequential nodes receive monotonically increasing sequence suffixes within the relevant namespace context and are useful for ordering recipes.
Ephemeral nodes disappear after session expiration and have restrictions appropriate to session-owned membership. Znode metadata includes versions that can be used for conditional updates/deletes, enabling optimistic coordination.
ACLs control access; they should be configured explicitly rather than assuming the coordination network is inherently trusted.