GOOSE Troubleshooter — “Why is my GOOSE not working?”

Load the SCD and a capture taken at the subscriber's switch port. For every GOOSE stream (or every stream a chosen subscriber uses), the troubleshooter compares what is on the wire with what the SCD says, check by check in the order a subscriber applies them — and tells you which check fails, why the subscriber then ignores the message, and what to change.

A GOOSE that does not arrive is the most common IEC 61850 commissioning problem, and the subscriber's indication ('missing', 'config mismatch') rarely says which of a dozen settings is wrong. The answer is almost always visible by comparing a capture with the SCD: wrong confRev, a VLAN not on the port, a simulation flag, a time allowed to live without margin. Doing that comparison field by field by hand takes long and is easy to get wrong.

Standards followed

IEC 61850-8-1 (GOOSE frame: APPID, gocbRef, timeAllowedtoLive, datSet, goID, stNum, sqNum, simulation, confRev, ndsCom, numDatSetEntries)IEC 61850-6 (GSE address: MAC, APPID, VLAN, priority, MinTime, MaxTime; GSEControl; ExtRef)IEC 61850-7-4 Ed2 (LPHD.Sim: simulated GOOSE)IEC 61850-90-4 (network engineering guidelines)

What it can do

Reads the GOOSE control blocks, their communication addresses, data sets and subscribers (ExtRef) from the SCD.
Decodes every GOOSE frame in a pcap / pcapng capture and groups them per stream.
Checks, per stream: present, destination MAC, APPID, VLAN, priority, gocbRef, goID, data set, confRev, number of entries, simulation / test, ndsCom, every frame within the previous frame's time allowed to live, publisher stopped, sqNum continuity, stNum changing with the data, quality of the values and time-stamp synchronisation.
Lists captured streams that are not in the SCD; filters to the streams one subscriber uses; adds guidance for the symptom you see.

Example problem

The demonstration bay: four GOOSE streams in the SCD and a five-second capture.

gcbTrip: one repetition arrives 48 ms after a frame that allowed 32 ms — the subscriber declares it lost.
gcbStatus: published with confRev 2 while the SCD says 3 (configuration mismatch), and silent for 3 s.
gcbIntlk: simulation bit and test set (ignored by a subscriber not in simulation), priority 1 instead of 4, a value change without a new stNum; gcbAlarm is not on the wire at all.

One clear cause per stream, with the fix: reload the CIDs from one SCD revision, take the test set out of simulation, check the switch path of gcbAlarm.

Capture at a mirror port of the subscriber's switch port (or as close as possible) so the capture sees what the subscriber sees. The capture shows the publisher side; the subscriber's own configuration (its CID, input mapping, simulation mode) must match the same SCD. Files are read in your browser.

SCD and capture

Open SCD…Open capture…

What do you see?

The subscriber reports the GOOSE as missing / lostThe subscriber reports a configuration mismatchThe subscriber receives it, but the value does not followIt works, then drops out from time to timeIt stopped after a change (new SCD, firmware, IED replaced)

Result

Open the SCD and a capture, or load a sample set.

Tool guide · know before you use

What this tool is, how it works and how far to trust it

A troubleshooter that finds why a GOOSE message is not accepted, by comparing a capture with the SCD for every GOOSE stream.

Read this before relying on a result. Every method, formula, assumption and limit is stated here, so you can check the answer yourself instead of accepting it blindly.

What it can do

Read the GOOSE control blocks, their addresses, data sets and subscribers from the SCD, and every GOOSE frame from a capture.
Check per stream, in the order a subscriber applies them: present on the wire, destination MAC, APPID, VLAN, priority, gocbRef, goID, data set reference, confRev, number of entries, simulation / test, ndsCom, each frame within the previous frame's time allowed to live, publisher stopped, sqNum continuity, stNum changing with the data, value quality, time-stamp synchronisation.
List streams on the wire that are not in the SCD, filter to one subscriber's streams, and give guidance for the symptom observed.

Why you need it

The subscriber's indication ('missing', 'config mismatch') does not say which of a dozen fields is wrong; comparing a capture with the SCD by hand is slow and error-prone.
Most GOOSE problems at commissioning are configuration differences between publisher, subscriber and switches — all visible in a capture.

Understand this first

A subscriber accepts a GOOSE only when MAC, APPID, gocbRef/goID, data set, confRev and the number of entries match its configuration, and the message is not simulated (unless the subscriber is in simulation).
Every GOOSE carries a time allowed to live: if the next message does not arrive within it, the subscriber declares the stream lost.
After a change of state the publisher repeats quickly (MinTime), then slows down to the heartbeat (MaxTime); stNum counts changes, sqNum counts repetitions.
GOOSE is layer 2: the VLAN must be carried by every switch port on the path.

What you need before you start

The SCD (the one the IEDs were configured from).
A capture (.pcap / .pcapng) taken at the subscriber's switch port, covering at least a few heartbeats.
A current browser (Chrome, Edge, Firefox or Safari). Nothing is installed and your data is never uploaded; it is processed on your own computer.

How to use it

Open the SCD and the capture (or load a sample set).
Optionally choose the subscriber and tick the symptoms you see.
Read each stream's checks: the first failed check is usually the cause; its note says what to change.

What you get

Per stream: a verdict, the SCD values and a table of checks with results, details and fixes; streams not in the SCD.

How to read the results

confRev, data set or entries differ: publisher and subscriber were configured from different SCD revisions — export and load both CIDs from one SCD.
Not on the wire: the publisher does not send (control block disabled, IED not configured) or the VLAN does not reach the capture point.
Late frames against the time allowed to live: frames lost or delayed, or a TAL set without margin.
Simulation / test: take the publisher or test set out of simulation, or put the subscriber in simulation for the test.

Technical basis

IEC 61850-8-1 GOOSE frame and acceptance rules; IEC 61850-6 GSE addresses and GSEControl; IEC 61850-7-4 Ed2 LPHD.Sim.
gocbRef is built as IED+LD/LLN0$GO$name; goID is the SCL appID (or gocbRef when absent); expected entries = FCDA count of the data set.

Limits: when not to rely on it

The capture shows the publisher side at one point; the subscriber's own configuration and input mapping cannot be seen.
GOOSE with IEC 62351-6 security or R-GOOSE over UDP are not decoded.

Sample files for this tool

Download, open and compare with what the guide says you should see.

GOOSE_SV_demo_bay1.pcap — One bay, five seconds — capture with deliberate faults
GOOSE_SV_demo_bay1.scd — SCD for the demonstration capture
S13_GOOSE_station_bus.pcap — S13 station bus GOOSE — capture for troubleshooting and the disturbance

All sample files and what to expect →

For preliminary engineering use. Results must be checked by a qualified engineer against the project's standards. How results are checked · Terms & disclaimer · Build 0473054 · 2026-11-14