This read-create OCTET STRING (0 or 8 bytes) specifies the LUN ID for LUN-level zoning on a zone member, with a zero-length string meaning LUN zoning is not configured; it cannot be configured when the member's zoneMemberFormat is 'fwwn', 'intf', or 'symNodeName', and cannot be modified while the member's row is active. Admins use it to restrict zoning down to specific LUNs on a storage target rather than the whole device. For example, an admin wanting to grant a host access to only one LUN on a shared storage array would set this object to that LUN's ID before activating the zone member row.