Linux stores users’ encrypted passwords, as well as other security information, such as account or password expiration values, in the /etc/shadow file. Someday you may need to edit the /etc/shadow file manually to set or change ones password.
If you try to upgrade salt-minions from the salt-master, in most cases salt-master would probably lose access to the minions. If the access is lost, you would have to log in to each host and restart the salt-minion service manually to make it communicate back with the salt-master. This problem is caused by the salt-minion […]
In salt, there is a useful file.managed state that can download files over HTTP/HTTPS and save them on the target system. Unfortunately for the moment it is not possible to download a file using salt in an normal way without knowing the file’s hash. If you try to download a file using salt state without […]
Sometimes it is required to merge several PDF files into a one PDF file. In Linux we can easily join multiple PDF files using the command line utility called convert that is a part of ImageMagick software suite. From this article you will learn how to merge entire PDF files into one PDF file or […]
The mod_wsgi is an Apache module that provides a WSGI compliant interface and serves for hosting Python based web applications under Apache (for example Django). To find out which version of mod_wsgi is installed or compiled, it is required to create a simple WSGI application. From the following article you will learn how to create […]
The mod_wsgi serves for hosting Python based web applications under Apache. This short article describes how to create a basic WSGI application and run it on Apache using mod_wsgi. Below you would find how to create a virtual host in Apache and publish a simple WSGI application that just prints “Hello World!”.
Apache has a lot of modules (or “mods”) that extend its core functionality for special purposes. How to list installed Apache modules – is a common question as it is very often required to check which Apache modules are loaded/enabled. List of installed Apache modules can be found using special option for httpd/apachectl (CentOS, RHEL […]
Telnet is a tool for connecting to servers on a given port for troubleshooting connection issues. One of the most common tasks that you can do via telnet – is connect to some web server and verify its health by checking the response code in HTTP header. Or you can get the content of a […]
A symbolic link, also known as a symlink or a soft link, is a special kind of file (entry) that points to the actual file or directory on a disk (like a shortcut in Windows). Symbolic links are used all the time to link libraries and often used to link files and folders on mounted […]
By default, the SSH client verifies the identity of the host to which it connects. If the remote host key is unknown to your SSH client, you would be asked to accept it by typing “yes” or “no”. This could cause a trouble when running from script that automatically connects to a remote host over […]