[SOLVED] MQTT not working after update to 2.4.0, connected, but no commands send or rec'd

Very similar to [SOLVED] MQTT not working after update to 2.4.0, connected, but no commands send or received but I have opened a new topic since this one was marked solved. The solution in the previous issue did not resolve mine.
After updating to 2.4.0 from 2.3.0 with Openhabian on Raspi2 I was able to get all of the zwave items working ok by following the published tips.
Mosquitto is a very different thing fthough. No commands are working and it seems no messages are being received with 2 ESP8266 devices that were working reliably prior to the upgrade. Even command line instructions are not getting a response.
What I have tried:
stop and re-start the mosquitto service
stop and re-start mqtt in Karaf console
uninstall and re-install mqtt in PaperUI followed by re-boot
did updates in openhabian-config noting that mosquitto updated to 1.4.10
re-selected mosquitto in openhabian-config
re-booted

It does not go to the cause of the issue but I noted that ‘systemctl status openhab2.service’ after re-boot shows ‘Active: inactive (dead)’ and requires the service to be started. This is a change from previous behaviour.

None of the above actions have restored mosquitto functions.
My item state
String livRMStr_blind1 “RollerBlind 1 [%s]” { mqtt="<[localbrokerrb:Blind1_esp/posn:state:default]" }
continues to remain “NULL”.

The mosquitto log contains:
1550533774: mosquitto version 1.4.10 (build date Wed, 13 Feb 2019 00:45:38 +0000) starting
1550533774: Config loaded from /etc/mosquitto/mosquitto.conf.
1550533774: Opening ipv4 listen socket on port 1883.
1550533774: Opening ipv6 listen socket on port 1883.
1550534193: New connection from ::1 on port 1883.
1550534194: Socket error on client , disconnecting.
1550534194: New connection from ::1 on port 1883.
1550534194: New client connected from ::1 as 5a037557-8e29-4086-b122-5f8e95dcbf74 (c1, k60).
1550534476: New connection from ::1 on port 1883.
1550534476: New client connected from ::1 as mosqpub/5058-openHABian (c1, k60).
1550534476: Client mosqpub/5058-openHABian disconnected.
1550534484: New connection from ::1 on port 1883.
1550534484: New client connected from ::1 as mosqpub/5063-openHABian (c1, k60).
1550534484: Client mosqpub/5063-openHABian disconnected.
1550534783: New connection from ::1 on port 1883.
1550534783: New client connected from ::1 as mosqpub/5712-openHABian (c1, k60).
1550534783: Client mosqpub/5712-openHABian disconnected.
1550534789: New connection from ::1 on port 1883.

Looks a bit like a KeepAlive timeout? Any clues to resolve this?

Solved it myself.
Uninstalled MQTT Persistence in PaperUI and then re-installed.
Uninstalled MQTT Action in PaperUI and then re-installed. Fixed.

1 Like

When updating to 2.4, the MQTTv1 binding is removed and the MQTTv2 binding is installed.
If you want to use your MQTT items as they are now you need to activate the 1.x compatibility in paperUI:

The re-install the MQTTv1 binding.

This binding will eventually be deactivated. So you will need to migrate your items to the MQTTv2 binding which works with things and channels:

Thanks for the reply. Looks like I will need to make a plan to update to the new binding.

Would have never expected it, but this fixed it for me as well. Delayed upgrade to 2.4 quite some time, but this was anyhow still an issue.

BTW: I saw openHAB already connecting, when uninstalling the “MQTT Action”, which surprised me, since then it works again. Reinstalled it as I need it. No further restarts needed.