Recently we faced a problem where Plesk was not accessible over Internet i.e. using port 8443 (https) and 8880 (normal). The first thing we checked was the Firewall; it happens sometime that the problem might be with firewall which was blocking port 8443 and 8880 but there was no problem with Firewall. Then we tried to check the status of Plesk (PSA) Service and got following response

[root@server ~]# /etc/init.d/psa status
psa dead but subsys locked


While checking for logs (Plesk Logs) on /usr/local/psa/admin/logs/error_log it was showing following Messages

[crit] (98)Address already in use: make_sock: could not bind to port 80


Now we have used command “/usr/sbin/lsof -i | grep http” (without quotes) and then killed the process using the ID. After that we have removed the Plesk Lock

[root@server ~]# rm -f /var/lock/subsys/psa


But starting Plesk service didn’t fixed the problem. Still we were getting “could not bind to port 80” Error.

Now we have opened Plesk Apache Configuration file which include Apache (Web Server) Configuration of Plesk Control Panel.

[root@vps ~]# vi /usr/local/psa/admin/conf/httpsd.conf


and found that the User has changed the Plesk Port and set it to listen on port 80 which is default port of HTTPD

# Listen: Allows you to bind Apache to specific IP addresses and/or
# ports, in addition to the default. See also the
# directive.
#
#Listen 3000
#Listen 12.34.56.78:80
#Listen 8443
#Listen 8880
Listen 80


So, we have made necessary changes httpsd.conf file i.e. disabled Port 80 and allowed 8443 and 8880 in Plesk Apache Configuration and restart PSA.

[root@vps ~]# /etc/init.d/psa start
Starting xinetd service… done
Starting named service… done
Starting mysqld service… done
Starting qmail service… done
Starting courier-imap service… done
Starting postgresql service… done
Starting psa-spamassassin service… done
Starting Plesk… done
Starting drwebd service… done
[root@vps ~]# /etc/init.d/psa status
httpsd (pid 1553 1529 1497 1492) is running…


NOTE:-
Here the problem was with Plesk Apache configuration but there might be some different problems too. I have posted this fix which will help to understand Plesk Error Log file and Plesk Apache Configuration files. If any of the USER face different problem and knows the FIX Let me know through Contact form I will be happy to post here.