HiveMQ cannot start

Question

I tried to start hivemq by moving to the bin folder and with command./run.sh, but I receive this message

ERROR - An error occurred while opening the retained_messages persistence. Is another HiveMQ instance running?

So I thought HiveMQ was already running, but when I open a browser and try to connect to http://localhost:8000 or http://localhost:1883 it does not connect. I also tried to open the Websocket client, but when I try to connect I receive this:

Connect failed: AMQJS0007E Socket error:undefined.

I have already tried to change port and restart, but nothing seems to change. Can somebody explain me what am I doing wrong and how to solve?

Answer 1

From my experience I know this log only occurs when an other instance is already running.

You might want to use the jps command to see if an other HiveMQ is already running (that will list all running java processes, should be installed with Java SDK)

Link to jps documentation: https://docs.oracle.com/en/java/javase/13/docs/specs/man/jps.html