Apache2 – IT Blog

Configuring OCSP Stapling

OCSP is a protocol for checking the validity of certificates, that is, to make sure that they have not been revoked and whether they were actually issued. Enabling OCSP Stapling on the web server side allows you to increase the speed of site opening, since the request to the certification authority is made not by the browser, but by the web server.

Solution Invalid command ‘Header’, perhaps misspelled or defined by a module not included in the server configuration

Once I transferred one site from one server to another Ubuntu server and after installing Apache2 I noticed the following error in the logs:

How to enable PHP-cURL

To enable the PHP-cURL extension on Linux Ubuntu/Debian, you must first install it with the command:

Solution AH00558: apache2: Could not reliably determine the server’s fully qualified domain name

Once after installing and configuring Apache2 on Ubuntu Server 20.04, I noticed the following error in the /var/log/apache2/error.log logs:

Configuring HTTPS in Apache

First, I will give an example of setting up HTTPS in Apache using a self-signed key.

Solution for ImportError: No module named web

Once I needed to disable the Nginx web server on the same server with iRedmail and install Apache2. And when I tried to start iRedadmin, it did not open, and in the Apache2 logs I saw:

Solution Syntax error on line 80 of /etc/apache2/apache2.conf: DefaultRuntimeDir must be a valid directory, absolute or relative to ServerRoot

Once I wanted to see which MPM module is being used and executed the command:

Installing Memcached

Let me give you an example of installing Memcached, which allows you to cache data in RAM.

How to get client IP address in logs instead of IP HAProxy

Once on the same server as HAProxy, I noticed that the server’s IP address is written in the logs, not the clients, or there’s simply no IP address at all and hyphens are displayed.

The problem with multiple SSL on the same IP

If there are several sites with SSL on the same IP address, then old ancient browsers that do not support SNI will not be able to determine which certificate to download and will most likely download the first one that is registered at the beginning of the web server configuration.