profinet-device-inventorylisted

## When to Use - A PROFINET island with no controller-supplied device list. - A segment that runs only PROFINET (Ethertype 0x8892) with no IP layer to scan. - A duplicate station name conflict reported by the IO controller. - Validating station names against the IO supervisor configuration. ## Prerequisites - tshark 4.x. Verify with `tshark --version`. - nmap 7.94 or newer with the `profinet-cm-lookup` NSE script. - SPAN port or network TAP on the island. - No IP address is required. DCP runs at Layer 2. - Credentials: none. - Authorization: segment owner sign-off. The DCP identity burst is an active Layer 2 step and needs a maintenance window. - Upstream skills: `passive-ot-network-discovery` for the segment capture. ### Safety This skill is passive by default. Active steps are gated in the Workflow section. - Passive. Captures and inspects traffic. Sends no packets. Safe to run during normal operations. ## Workflow 1. Resolve the DCP field names for this tshark revision: `tshark -G fields | grep -i nameofstation` `tshark -G fields | grep -i pn_dcp` Field names change across tshark releases. Use the resolved names in the commands below. 2. Passive device list from a capture that holds controller boot or address-resolver traffic: `tshark -r capture.pcapng -Y "pn_dcp" -T fields -e eth.src -e <nameofstation-field> | sort -u > dcp_devices.txt` 3. Decision point: if no DCP frames exist in the capture, the island has no station naming traffic in the window. Do