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sslmqtttls1.2

MQTT server with SSL/TLS Error: Unable to load server key file

I am trying to set up an MQTT broker with SSL. When I start the broker, I get this error:

1452342536: Error: Unable to load server key file "/home/ilab/mqtt/server/server.key". Check keyfile.

The following is my mosquitto.conf:

pid_file /var/run/mosquitto.pid
persistence true
persistence_location /var/lib/mosquitto/
log_dest file /var/log/mosquitto/mosquitto.log
include_dir /etc/mosquitto/conf.d
cafile /home/ilab/mqtt/CA/ca.crt
certfile /home/ilab/mqtt/server/server.crt
keyfile /home/ilab/mqtt/server/server.key
port 8883
tls_version tlsv1

I also followed the step mentioned in THIS question. But still didn't solve the problem.

Solution

  • I had similar issue and it seems like it got fixed by changing the permissions to read the file from: -rw------- to -rw-r--r-- for the file /etc/mosquitto/certs/mqtt-server.key

    Steps:

    • Navigate to the directory
    cd /etc/mosquitto/certs
    • List file permissions (-rw-------)
    ls -l
    • As root, change all users permission to read the file
    sudo chmod a+r mqtt-server.key
    • List file permissions again to see changes (now -rw-r--r--)
    ls -l
    • Restart the broker/server
    sudo systemctl restart mosquitto

    I not sure if this pose any security issue, but hope not. Planning on using authorization and encryption to access the server from the web.