yes exactly i followed the same steps as per instruction.
This is mosquitto.conf file results.
Place your local configuration in /etc/mosquitto/conf.d/
A full description of the configuration file is at
/usr/share/doc/mosquitto/examples/mosquitto.conf.example
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
I believe that i have to add some line of code, in order to run mosquitto_sub