How to access the fresh installation of ISPConfig 3 in VPS?

I followed The Perfect Server - Ubuntu 18.04... to install ISPConfig and the installation completed successfully, however trying to access the ISPConfig admin area from IP-ADDRESS:8080 results into error [ERR_CONNECTION_TIMED_OUT]. I am able to access the default apache2 web page from the IP-ADDRESS though. Where did I go wrong?
The IP-ADDRESS used is static and accessible publicly. During the installation process, FQDN is entered as abc.xyz.com which is obtained from ping to the IP-ADDRESS.

Checking for Common issues shows that ISP Config 3.1.15p3 is installed, screenshot attached below.
Checking for active internet connections (by running a netstat -tap) is not showing any program name related to ispconfig.

 

Yes, port 8080 is open in the firewall.
the output of sites-available is as follows.

Code:

 000-default.conf  apps.vhost  default-ssl.conf  ispconfig.conf  ispconfig.vhost 

Now I am getting internal server error without any error code after several reboots.

Code:

 
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator at webmaster@localhost to inform them of the time this error occurred, and the actions you performed just before this error.

More information about this error may be available in the server error log. 

 

I could not find any useful information in the logs.

yes, all the steps are run as stated.

 

When the installer asked about

Code:

ISPConfig Port [8080]:

did you change it from 8080?
What port is defined in ispconfig.vhost?

 

I simply pressed enter without changing port.
ispconfig.vhost has port 8080 defined as

Code:

 Listen 8080
NameVirtualHost *:8080

<VirtualHost _default_:8080>
  ServerAdmin webmaster@localhost

  <Directory /var/www/ispconfig/>
    <FilesMatch "\.ph(p3?|tml)$">
      SetHandler None
    </FilesMatch>
  </Directory>
  <Directory /usr/local/ispconfig/interface/web/>
    <FilesMatch "\.ph(p3?|tml)$">
      SetHandler None
    </FilesMatch>
  </Directory>

 

Here is the report script

Code:

##### SERVER #####
IP-address (as per hostname): ***.***.***.***
[WARN] could not determine server's ip address by ifconfig
[INFO] OS version is Ubuntu 18.04.5 LTS

[INFO] ISPConfig is installed.

##### ISPCONFIG #####
ISPConfig version is 3.1.15p3


##### VERSION CHECK #####

[INFO] php (cli) version is 7.2.24-0ubuntu***.***.***.***

##### PORT CHECK #####

[WARN] Port 465 (SMTP server SSL) seems NOT to be listening

##### MAIL SERVER CHECK #####

[WARN] I found no "submission" entry in your postfix master.cf
[INFO] this is not critical, but if you want to offer port 587 for smtp connections you have to enable this.
[WARN] I found no "smtps" entry in your postfix master.cf
[INFO] this is not critical, but if you want to offer SSL for smtp (not TLS) connections you have to enable this.

##### RUNNING SERVER PROCESSES #####

[INFO] I found the following web server(s):
        Apache 2 (PID 1375)
[INFO] I found the following mail server(s):
        Postfix (PID 1347)
[INFO] I found the following pop3 server(s):
        Dovecot (PID 927)
[INFO] I found the following imap server(s):
        Dovecot (PID 927)
[INFO] I found the following ftp server(s):
        PureFTP (PID 1609)

##### LISTENING PORTS #####
(only           ()
Local           (Address)
[anywhere]:993          (927/dovecot)
[anywhere]:10050                (786/zabbix_agentd)
[anywhere]:995          (927/dovecot)
[localhost]:10023               (1385/postgrey)
[localhost]:10024               (1631/amavisd-new)
[localhost]:10025               (1347/master)
[localhost]:10026               (1631/amavisd-new)
[localhost]:10027               (1347/master)
[localhost]:11211               (916/memcached)
[anywhere]:110          (927/dovecot)
[anywhere]:143          (927/dovecot)
[anywhere]:21           (1609/pure-ftpd)
***.***.***.***:53              (812/named)
[localhost]:53          (812/named)
***.***.***.***:53              (654/systemd-resolve)
[anywhere]:22           (1099/sshd)
[anywhere]:25           (1347/master)
[localhost]:953         (812/named)
[anywhere]:1883         (1037/mosquitto)
*:*:*:*::*:993          (927/dovecot)
[localhost]0050         (786/zabbix_agentd)
*:*:*:*::*:995          (927/dovecot)
*:*:*:*::*:10023                (1385/postgrey)
*:*:*:*::*:10024                (1631/amavisd-new)
*:*:*:*::*:10026                (1631/amavisd-new)
*:*:*:*::*:3306         (1260/mysqld)
[localhost]10           (927/dovecot)
[localhost]43           (927/dovecot)
*:*:*:*::*:8080         (1375/apache2)
*:*:*:*::*:80           (1375/apache2)
*:*:*:*::*:8081         (1375/apache2)
*:*:*:*::*:21           (1609/pure-ftpd)
*:*:*:*::*:53           (812/named)
*:*:*:*::*:22           (1099/sshd)
*:*:*:*::*:25           (1347/master)
*:*:*:*::*:953          (812/named)
*:*:*:*::*:443          (1375/apache2)
[localhost]883          (1037/mosquitto)




##### IPTABLES #####
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
f2b-sshd   tcp  --  [anywhere]/0            [anywhere]/0            multiport dports 22

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         

Chain f2b-sshd (1 references)
target     prot opt source               destination         
REJECT     all  --  ***.***.***.***       [anywhere]/0            reject-with icmp-port-unreachable
REJECT     all  --  ***.***.***.***        [anywhere]/0            reject-with icmp-port-unreachable
REJECT     all  --  ***.***.***.***        [anywhere]/0            reject-with icmp-port-unreachable
REJECT     all  --  ***.***.***.***        [anywhere]/0            reject-with icmp-port-unreachable
REJECT     all  --  ***.***.***.***      [anywhere]/0            reject-with icmp-port-unreachable
RETURN     all  --  [anywhere]/0            [anywhere]/0           

If I am about to install ISPConfig in a cloud VPS with a static public IP address, what would be the required FQDN entries? I have entered the domain name abc.xyz.com which is returned while pinging provided public IP address.

 

I am using the same method to access the installed ISPConfig. https://IPADDRESS:8080

So If I want to make it accessible from IP Address only, I don't have to enter any FQDN during installation right?

 

Thank you for the support will proceed with reinstalling a VM and start again the procedure carefully. Thanks Again