Windows: MQTT protocol connections dont work when too many websocket connections

[sectokia]

I have a problem with v2 on windows, where once too many websocket clients connect, the MQTT protocol listener won't accept connections anymore.

Here is a reliable procedure to reproduce:
-Connect a client via protocol MQTT.
-Connect 72 clients via protocol Websocket (I verify more than 64 at once by waiting for PINGREQ/PINGRESP, how is this possible, I thought the limit was 64?)
-Kill the client connected via MQTT, and wait for mosquitto to timeout disconnect it.
-Start any MQTT client again on MQTT protocol. All clients I've tried report a connack timeout, and there is no "New connection" ever reported in the log.
-Even if you then disconnect all 72 websocket clients, you still cannot connect via MQTT protocol anymore. Only way I've found to fix it is to restart mosquitto.

Invocation:
mosquitto -c ..\config\mosquitto.conf > ..\log\mosquitto.log
This is my conf:

###########################################
per_listener_settings true
allow_zero_length_clientid true
auto_id_prefix auto-
check_retain_source true
persistent_client_expiration 1m
retain_available true
sys_interval 10
autosave_interval 1800
autosave_on_changes false
persistence true
persistence_file mosquitto.db
log_dest stdout
log_type all
connection_messages true
log_timestamp true
log_timestamp_format %Y-%m-%dT%H:%M:%S

###########################################
listener 1883
protocol mqtt
allow_anonymous false
password_file ..\config\mosquitto.pw.conf
acl_file ..\config\mosquitto.acl.conf

##########################################
listener 8083
protocol websockets
allow_anonymous false
password_file ..\config\mosquitto.pw.conf
acl_file ..\config\mosquitto.acl.conf
http_dir ..\www

[ralight]

The 64 client limit must no longer apply due to changes in libwebsockets.

I'll try and see if I can reproduce your problem in Windows.

[sectokia]

I have tried on more windows systems, and found several where once any websocket is connected, mqtt doesn't work at all?
Maybe I am doing something fundamentally wrong.

Here is my simple setup, Windows10 with mosquitto-2.0.0-install-windows-x64.exe installed.

mosquitto.conf is:

listener 1883
protocol mqtt
allow_anonymous true

listener 8083
protocol websockets
allow_anonymous true

run mosquitto:
mosquitto -c mosquitto.conf -v

output shows:

1607511019: mosquitto version 2.0.0 starting
1607511019: Config loaded from mosquitto.conf.
1607511019: Opening ipv6 listen socket on port 1883.
1607511019: Opening ipv4 listen socket on port 1883.
1607511019: Opening websockets listen socket on port 8083.
1607511019: mosquitto version 2.0.0 running

publish works as expected:
mosquitto_pub -t test -m hello
output is:

1607511044: New connection from ::1:52150 on port 1883.
1607511044: New client connected from ::1:52150 as auto-8B60F39F-504D-7C75-DEDC-B5A7B34F58AB (p2, c1, k60).
1607511044: No will message specified.
1607511044: Sending CONNACK to auto-8B60F39F-504D-7C75-DEDC-B5A7B34F58AB (0, 0)
1607511044: Received PUBLISH from auto-8B60F39F-504D-7C75-DEDC-B5A7B34F58AB (d0, q0, r0, m0, 'test', ... (5 bytes))
1607511044: Received DISCONNECT from auto-8B60F39F-504D-7C75-DEDC-B5A7B34F58AB
1607511044: Client auto-8B60F39F-504D-7C75-DEDC-B5A7B34F58AB disconnected.

now connect websocket (I'd did it via mqttjs) and subscribe to topic 'test'
Works as expected:

1607511089: New client connected from 127.0.0.1:52170 as mqttjs_a68fd89c (p2, c1, k60).
1607511089: No will message specified.
1607511089: Sending CONNACK to mqttjs_a68fd89c (0, 0)
1607511089: Received SUBSCRIBE from mqttjs_a68fd89c
1607511089:     test (QoS 0)
1607511089: mqttjs_a68fd89c 0 test
1607511089: Sending SUBACK to mqttjs_a68fd89c

now try and publish again on mqtt:

mosquitto_pub -t test -m hello -d
Client (null) sending CONNECT

Nothing happens.... after a long time mosquitto_pub outputs:
Error: Unknown error.

If you disconnect the websocket before that error, the publish suddenly works.

Repeat exact same procedure with version 1.6.9 - everything works fine - publish is able to work even when a websocket is connected.

[ralight]

I believe this is now fixed, it will be part of 2.0.1.

[sectokia]

Thank you, when would 2.0.1 likely come out?
This effects both windows versions of 2.0.0
So on windows right now you can only use mosquitto 2.0.0 with one protocol

[jarapa9]

@sectokia was the issue resolved for you? For me the upgrade to Windows version 2.0.2 did not resolve those symptoms.

[sectokia]

Is anyone able to write a breif tutorial of how to setup to compile moqusitto for windows?

I know C, but I have no idea how to get the toolchain going to compile. On linux its so simple and I'm able to run and debug fine.

On windows however I have no idea what I am doing. I installed visual studio and opened the source code folder in visual studio, which did trigger cmake to do... something. But I have no idea where to go from there.

Anyone know how to: make a 'project' for so you can just hit compile/run/debug etc?
Install OpenSSL and Libwebsockets form source as well?

[sectokia]

This issue still occurs as of 2.0.3a.

Is there any instructions for how to compile on windows anywhere?