World Wide Name (WWN) is a globally unique identifier, commonly 64 or 128 bits, used in Fibre Channel networks to identify ports and nodes.
Simple definition
World Wide Name (WWN) is a globally unique identifier, commonly 64 or 128 bits, used in Fibre Channel networks to identify ports and nodes. It belongs to the Storage vocabulary and is useful when reading architecture diagrams, product documentation, logs, or administration procedures.
What is it used for?
Its main purpose is to stably identify initiators, targets, and ports for SAN zoning, masking, and troubleshooting. The practical value depends on the surrounding architecture, security model, and operational requirements.
How does it work?
An HBA typically has a WWNN for the node and WWPNs for its ports. Switches and arrays use these identifiers in their policies.
Key points
- Scope: A globally unique identifier, commonly 64 or 128 bits, used in Fibre Channel networks to identify ports and nodes.
- Operational goal: Stably identify initiators, targets, and ports for SAN zoning, masking, and troubleshooting.
- Implementation: An HBA typically has a WWNN for the node and WWPNs for its ports. Switches and arrays use these identifiers in their policies.
Points to watch
Document topology and dependencies before changes; a pool, tiering, or multipath mistake can cause access loss or severe degradation.
In short
World Wide Name (WWN) = a globally unique identifier, commonly 64 or 128 bits, used in Fibre Channel networks to identify ports and nodes. Use it when you need to stably identify initiators, targets, and ports for SAN zoning, masking, and troubleshooting.