Redirect a subdomain in Apache and keep the URL in the address bar

Apache Redirect

This tutorial shows you how to use redirect rules in the Apache web server. If you want to redirect a subdomain like sub.domain.tld into a subdirectory of the website and keep the original URL in the browser location bar, you may use the following apache directive. RewriteEngine on RewriteCond %{HTTP_HOST} ^sub.domain.tld [NC] RewriteRule ^/(.*)$ /sub/$1 ... Read more

How to access a name based website without a DNS record

Hosts file

If you want to access a name-based website that you created e.g. in ISPConfig before the DNS records are set up, edit the hosts file on your workstation computer and add a line like this: 192.168.0.100        www.mydomain.com mydomain.com Edit hosts file on macOS X To edit the hosts file on a computer running macOS X, ... Read more

[Solved] Postfix: “queue file write error”

Postfix: Queue File Write Error

If you get an error like: Apr 15 12:41:03 webb4 postfix/sendmail[11234]: fatal: web1_user(12967): queue file write error in your mail log, then the value for message_size_limit in postfix main.cf is too low. Solve Postfix queue file write error Edit postfix main.cf: nano /etc/postfix/main.cf and set the message size limit to a higher value. E.g. message_size_limit ... Read more

How to enable verbose logging in pure-ftpd on Debian and Ubuntu

PureFTPD Verbose Log

To turn on verbose logging (e.g. to debug FTP connection or authentication problems) in pure-ftpd FTP server on Debian and Ubuntu Linux. Enable debug log in pure-ftpd Execute the following command as root user in the shell to enable verbose logging: echo 'yes' > /etc/pure-ftpd/conf/VerboseLog and then restart pure-ftpd, for init based systems: service pure-ftpd-mysql ... Read more

Configure fail2ban to use route instead of iptables to block connections

Fail2ban route command

Fail2ban uses iptables by default to block incoming connections when they exceed the max.  login retries. The iptables rules used by fail2ban might conflict with other firewall rules, so it might be necessary to reconfigure fail2ban to use the route command for blocking incoming connections. Fail2ban ban using route command To reconfigure fail2ban for using ... Read more

Redirect domains without www (e.g. domain.com) to www.domain.com with apache rewrite rules

Apache www redirect rule

If all your visitors shall access your website with a URL like www.domain.com and not without www, use the following apache rewrite rule for redirecting them. RewriteEngine On RewriteCond %{HTTP_HOST} !^www RewriteRule (.*) http://www.%{HTTP_HOST}$1 [L,R] The apache rewrite rule can be added in a .htaccess file in the website root directory or if you use ... Read more

How to enable DKIM email signatures in amavisd-new and ISPConfig 3.0

NOTE: This post is about ISPConfig 3.0 and not 3.1 and newer. ISPConfig 3.1 and newer has DKIM support builtin, you can simply enable DKIM in ISPConfig 3.1 GUI now for the mail domain. DKIM is a system to verify the sender and integrity of emails. ISPConfig 3 uses amavisd-new as content filter for spam ... Read more