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

Question

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.

Answer 1

As @hardillb implies, try removing the password or start the broker manually.

Alternatively, if you're on Ubuntu then apparmor may be restricting access to those files. Try put them in /etc/mosquitto/certs instead.