UDP Send and receive when using node red in docker container

General
1

Hi There,

I'm trying to send and receive massages via UDP with two Node-Red instances installed via Docker containers.

Flows on instance 1:

[
    {
        "id": "3affecfb.85c07c",
        "type": "inject",
        "z": "3fccb497.9b16f4",
        "name": "",
        "topic": "",
        "payload": "",
        "payloadType": "date",
        "repeat": "",
        "crontab": "",
        "once": false,
        "onceDelay": 0.1,
        "x": 320,
        "y": 160,
        "wires": [
            [
                "8cf7dc9a.c37c7"
            ]
        ]
    },
    {
        "id": "311c30f9.5930d8",
        "type": "udp in",
        "z": "3fccb497.9b16f4",
        "name": "",
        "iface": "",
        "port": "2001",
        "ipv": "udp4",
        "multicast": "false",
        "group": "",
        "datatype": "buffer",
        "x": 320,
        "y": 260,
        "wires": [
            [
                "41fca546.e83e2c"
            ]
        ]
    },
    {
        "id": "41fca546.e83e2c",
        "type": "debug",
        "z": "3fccb497.9b16f4",
        "name": "",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "true",
        "targetType": "full",
        "x": 490,
        "y": 260,
        "wires": []
    },
    {
        "id": "8cf7dc9a.c37c7",
        "type": "udp out",
        "z": "3fccb497.9b16f4",
        "name": "",
        "addr": "192.168.2.101",
        "iface": "",
        "port": "1999",
        "ipv": "udp4",
        "outport": "2000",
        "base64": false,
        "multicast": "false",
        "x": 600,
        "y": 160,
        "wires": []
    }
]

Flow on Instance 2:

[
    {
        "id": "3e48491b.09f93e",
        "type": "udp in",
        "z": "5ea6d14d.86d94",
        "name": "",
        "iface": "",
        "port": "1999",
        "ipv": "udp4",
        "multicast": "false",
        "group": "",
        "datatype": "buffer",
        "x": 220,
        "y": 340,
        "wires": [
            [
                "12cc1018.37d628"
            ]
        ]
    },
    {
        "id": "12cc1018.37d628",
        "type": "debug",
        "z": "5ea6d14d.86d94",
        "name": "",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "false",
        "x": 450,
        "y": 340,
        "wires": []
    },
    {
        "id": "45d00fe0.41e258",
        "type": "inject",
        "z": "5ea6d14d.86d94",
        "name": "",
        "topic": "",
        "payload": "",
        "payloadType": "date",
        "repeat": "",
        "crontab": "",
        "once": false,
        "onceDelay": 0.1,
        "x": 220,
        "y": 300,
        "wires": [
            [
                "f01672f5.c1bee8"
            ]
        ]
    },
    {
        "id": "f01672f5.c1bee8",
        "type": "udp out",
        "z": "5ea6d14d.86d94",
        "name": "",
        "addr": "192.168.2.111",
        "iface": "",
        "port": "2001",
        "ipv": "udp4",
        "outport": "",
        "base64": false,
        "multicast": "false",
        "x": 490,
        "y": 300,
        "wires": []
    }
]

Wireshark picture, of what happens:

image
image.png987×106 20.1 KB

So what I expected was sending and receiving from one to the other... :slight_smile:
but that doesn't happen.

Docker Statement on both instances: (running on two different pi's) same network, static IP's

docker run -d -p1880:1880 --name nodered echteler/nodered:arm32v7

so I hope for some help fixing the issue :slight_smile:

Thank You very much for Your help :slight_smile:

2

Did you map the (udp) ports in the docker containers ?

3

nope, not yet... from what I read, that should not be neccesary. But I'll try that right now.

4

Just in Case someone has the same issues :slight_smile:

I added the Port mappings according to the ports I want to use :slight_smile:

docker run -d -p 1881:1880 -p 2001:2001/udp -p 1998:1998/udp --name nodered3 ...