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Ubuntu Server 18.04 ; SSL/TLS applied to web , mail , FTP server

1. Apache2 : SSL/TLS Configuration

Describes how to apply an SSL certificate obtained with Let's Encrypt to apache.
Domain name :

1.1 Configuration of Apache2

①Editing the Apache2 configuration file
Rename and copy the default conf file (e.g. "")


Default disable

②Enable the SSL module

Restart Apache2

1.2 http to https redirection

①How to create an ".htaccess" file

Create a .htaccess file in /var/www/html/ and fill in the following

②How to fill in

②Settings reflect

2.Mail Server : SSL/TLS Settings

Configure SSL/TLS settings to enable encrypted communication.
SMTPS uses 465/TCP, POP3S uses 995/TCP, IMAPS uses 993/TCP

2.1 Setting up a virtual host and obtaining a certificate for mail

①Virtual Host Settings for Mail Hosts

②Create directory

③Obtaining a letsencrypt SSL Certificate

2.2 Postfix Configuration

①Edit "".

②Edit "".

③Check the settings for errors.

If nothing appears, it's OK.

④Postfix startup and auto-start

2.3 Configuring Dovecot

① Edit "10-ssl.conf".

② Edit "10-master.conf".

③Setting the authentication method

④Specify the location of the mailbox.

⑤Change the output destination of the log

⑥Create log output destination

⑦Start Dovecot and configure it to start automatically.

⑧Verify that the authentication socket file has been created.

3.Set up SSL/TLS on the FTP server.

Encrypt ftp transfers with Let's Encrypt obtained from Web Server Encryption.

3.1 Vsftpd Configuration

①Configuration file editing

②Restart Vsftpd

3.2 Firewall Settings

Allow fixed PASV ports other than ftp ports