[Solved] [v8.1.0] Mattermost Calls plugin not working

Troubleshooting
1

Summary
Mattermost Calls can not establish a connection

Steps to reproduce
How can we reproduce the issue (what version are you using?)

  • start a call
  • it’s irrelevant whether another user tries to join or not, the call can’t be started

Mattermost Server version: 8.1.0
Mattermost Client version: 5.4.0
ICE Host Override variable = Server FQDN (only IPv4 A record present, no IPv6 AAAA record)

Expected behavior

  • call should be started

Observed behavior

  • call can’t be started

desktop client message:

Connection failed
There was an error with the connection to the call. Try to [re-join](https://URL/TEAM/messages/@USER) the call. Check the [troubleshooting section](https://docs.mattermost.com/channels/make-calls.html#troubleshooting) if the problem persists.

Logfile:

{"timestamp":"2023-08-28 11:04:50.568 +02:00","level":"info","msg":"AddConn: tcp remote CLIENT1:63775 to local MMSERVER:8443","caller":"app/plugin_api.go:973","plugin_id":"com.mattermost.calls","origin":"main.(*logger).Info log.go:95"}
{"timestamp":"2023-08-28 11:04:56.741 +02:00","level":"info","msg":"AddConn: tcp remote CLIENT2:60645 to local MMSERVER:8443","caller":"app/plugin_api.go:973","plugin_id":"com.mattermost.calls","origin":"main.(*logger).Info log.go:95"}
{"timestamp":"2023-08-28 11:05:05.602 +02:00","level":"info","msg":"error reading streaming packet: read tcp4 MMSERVER:8443->CLIENT1:63775: use of closed network connection","caller":"app/plugin_api.go:973","plugin_id":"com.mattermost.calls","origin":"main.(*logger).Info log.go:95"}
{"timestamp":"2023-08-28 11:05:05.602 +02:00","level":"warn","msg":"error closing connection: close tcp4 MMSERVER:8443->CLIENT1:63775: use of closed network connection","caller":"app/plugin_api.go:979","plugin_id":"com.mattermost.calls","origin":"main.(*logger).Warn log.go:99"}
{"timestamp":"2023-08-28 11:05:05.700 +02:00","level":"error","msg":"callback failed: not found","caller":"app/plugin_api.go:976","plugin_id":"com.mattermost.calls","origin":"main.(*Plugin).handleLeave websocket.go:455"}
{"timestamp":"2023-08-28 11:05:11.755 +02:00","level":"info","msg":"error reading streaming packet: read tcp4 MMSERVER:8443->CLIENT2:60645: use of closed network connection","caller":"app/plugin_api.go:973","plugin_id":"com.mattermost.calls","origin":"main.(*logger).Info log.go:95"}
{"timestamp":"2023-08-28 11:05:11.755 +02:00","level":"warn","msg":"error closing connection: close tcp4 MMSERVER:8443->CLIENT2:60645: use of closed network connection","caller":"app/plugin_api.go:979","plugin_id":"com.mattermost.calls","origin":"main.(*logger).Warn log.go:99"}
{"timestamp":"2023-08-28 11:05:11.810 +02:00","level":"error","msg":"callback failed: call state is missing from channel state","caller":"app/plugin_api.go:976","plugin_id":"com.mattermost.calls","origin":"main.(*Plugin).handleLeave websocket.go:455"}
2

Gladly we could fix the problem. We had to set the following config setting (because our servers each have a management + productive IP):

"com.mattermost.calls": {
(...)
                "tcpserveraddress": "<productive IP>",
                "udpserveraddress": "<productive IP>",
(...)
            },