"Disconnected" state with Growatt 5500MTL-S / ShineLAN

[Rubeast]

I have a Growatt 5500MTL-S that has a ShineLAN data logger via RS232.

I have installed grott via docker with all the default values. My MQTT runs on the same server, but I've defined the IP to be sure.
Docker compose file that I use:

  grott:
    container_name: grott
    image: ledidobe/grott:latest
    restart: unless-stopped
    ports:
      - "5279:5279"
    environment:
      - TZ=Europe/Brussels
      - gmqttip=192.168.10.3

If I test port 5279 from my PC (With PS command "Test-NetConnection 192.168.10.3 -p 5279", I see the attempt in the grott logs.

	version:             	 2.7.8
	verbose:             	 True
	trace:               	 False
	config file:         	 grott.ini
	minrecl:             	 100
	decrypt:             	 True
	compat:              	 False
	invtype:             	 default
	invtypemap:          	 {}
	include_all:         	 False
	blockcmd:            	 False
	noipf:               	 False
	time:                	 auto
	sendbuf:             	 True
	timezone:            	 local
	valueoffset:         	 6
	offset:              	 6
	inverterid:          	 automatic
	mode:                	 proxy
	grottip              	 default
	grottport            	 5279
_MQTT:
	nomqtt               	 False
	mqttip:              	 192.168.10.3
	mqttport:            	 1883
	mqtttopic:           	 energy/growatt
	mqttmtopic:          	 False
	mqttmtopicname:      	 energy/meter
	mqttinverterintopic: 	 False
	mqtttretain:         	 False
	mqtttauth:           	 False
	mqttuser:            	 grott
	mqttpsw:             	 **secret**
_Growatt server:
	growattip:           	 47.91.67.66
	growattport:         	 5279
_PVOutput:
	pvoutput:            	 False
	pvdisv1:             	 False
	pvtemp:              	 False
	pvurl:               	 https://pvoutput.org/service/r2/addstatus.jsp
	pvapikey:            	 yourapikey
	pvinverters:         	 1
	pvsystemid:          	 systemid1
_Influxdb:
	influx:             	 False
	influx2:            	 False
	database:           	 grottdb
	ip:                 	 localhost
	port:               	 8086
	user:               	 grott
	password:           	 **secret**
	organization:       	 grottorg
	bucket:             	 grottdb
	token:              	 **secret**
_Extension:
	extension:          	 False
	extname:            	 grottext
	extvar:             	 {'none': 'none'}
Grott proxy mode started
Hostname : MiniBox
IP :  127.0.1.1 , port :  5279 
	 - ('192.168.2.200', 55322) has connected
	 - ('192.168.2.200', 55322) has disconnected

I seems that the interface of my datalogger is a bit different then other screenshots I've seen. But this is the error I'm getting.
Also, this attempt is not appearing in the logs.

[Rubeast]

I was able to find a solution. I doubt that many other people will run into the same issue, but here it is:

My docker server has IP 192.168.10.3, which puts it in the 192.168.10.0/24 network.
The ONLY network the datalogger is unable to contact is 192.168.10.0/24 !

It turns out that the datalogger has a built-in AP interface using a hardcoded IP address: 192.168.10.100. Because this IP falls within the 192.168.10.0/24 range, the device treats all traffic to that subnet as internal traffic.

So this stupid configuration decision of Growatt is the reason I could not get it to work!

Since I didn’t want to move my docker server to a different subnet, I created a port-forwarding rule on my router:

• Protocol | TCP
• Source | 192.168.5.0/24 (range of my datalogger)
• Forward IP | 192.168.10.3 (IP of my server)
• Forward Port | 5279
• WAN Port | 5279

After that, you can set your WAN IP (or domain name) as the server address on the datalogger.
And finally after 6 months, it works!