Sometimes you might want to block connects to your server by IP address. E.g. when someone tries to attack your system. This can be done in several different ways, e.g. with iptables (firewall) rules or by setting up a reject route. Reject access with Linux route command Using iptables sometimes causes conflicts with installed firewalls ... Read more
This short guide shows you how to get a list of all installed Packages on Debian Linux. Packages on Debian get installed with the apt package installer. We will use the dpkg command, which is part of the apt toolset, to query the installed packages database. Get all installed Debian packages dpkg --get-selections As you ... Read more
Sometimes it is necessary to limit the download rate of the wget command, e.g. when you are downloading a large file over a slow internet connection. Wget Command Download Limit The parameter to apply a download speed limit is the --limit-rate option. This setting is followed by the rate limit plus "k" for Kbit or ... Read more
The Linux TigerVNC Server provides a command to set a new password. Set VNC Password The command is "vncpasswd", the password is stored in encrypted form into the file ~/.vnc/passwd of the home directory of the user. Run: vncpasswd to set a new password for the currently logged-in user. The command will then prompt for the ... Read more
This guide shows you how to kill an unresponsive OpenVZ container in case the normal stop procedure fails. Killing the container will not delete any files or remove the container, it just kills all processes so that you can start or restart the container again when it gets stuck. I will use container ID 101 ... Read more
It is important to keep your Linux server up to date with security updates. Linux distributions like Ubuntu and Debian release updates on a daily basis, so keeping the system up-to-date can become a tedious task. Fortunately, there is an option to install security updates automatically. Here are the steps to enable automatic security updates ... Read more
Sometimes, you might want to apply a chmod to files only and not directories. This guide shows you three different ways to achieve that goal on the Linux command line. How to chmod files only One of the easiest ways is to use the find command to select the files and then run the chmod command with ... Read more
There is no simple 'tolower' command on the bash, but you can convert uppercase characters to lowercase with a little shell script. The script uses the tr command internally for converting the chars. Create a shell script with the name 'tolower' that converts all text that is given as a command-line argument to lower case: ... Read more
One way to create a backup of a MySQL database on the shell is to use the mysqldump command. Mysqldump creates a dump of the database in form of sql commands, which can be easily restored using the mysql command or PHPMyAdmin. Backup a MySQL Database mysqldump -u root -p mydatabase > /tmp/backup_mydatabase.sql This command ... Read more
This short guide shows you how to add a newline into a file by using the echo command on the Linux shell. Add a Newline Character using echo command in Bash In this example, I'll assume that we have a file example.txt with the following content: Line 1 Line 2 Now we want to use ... Read more