If you want to extract digits from a string in bash, you can use the following methods: Using grep: string=”abc123def456″ digits=$(echo $string | grep -o ‘[0-9]\+’) echo $digits Output: 123456 Using sed: string=”abc123def456″ digits=$(echo $string | sed ‘s/[^0-9]*//g’) echo $digits Output: 123456 Using awk: string=”abc123def456″ digits=$(echo $string | awk ‘/[0-9]+/{ gsub(/[^0-9]+/, “”, $0); print $0 … Read more
To disable or remove all NFS services on Debian/Ubuntu Linux, you can use the following steps: Stop the NFS server service: sudo service nfs-kernel-server stop Disable the NFS server service from starting automatically during boot: sudo update-rc.d nfs-kernel-server disable Uninstall the NFS server packages: sudo apt-get remove nfs-kernel-server Repeat the above steps for any other … Read more
To show lines in the vi or vim text editor, you can enable line numbers by using the following command: :set number This will display line numbers in the editor, and you can turn off line numbers by using the following command: :set nonumber Alternatively, you can enable line numbers when launching vi or vim … Read more
The easiest way to generate a random password in Linux is to use the “openssl” command. The following command will generate a 12-character random password: openssl rand -base64 12 This generates a random string of 12 characters that is base64-encoded, which gives you a set of characters that are safe to use in a password. … Read more
To remove a non-empty directory in Unix/Linux, you can use the rm command with the -r option. This option tells rm to remove the specified directory and all of its contents, including subdirectories and files. Here’s the syntax for using rm to remove a non-empty directory: rm -r directory_name For example, if you wanted to … Read more
To merge Apache / Lighttpd / Nginx server log files, you can use the cat command in Linux/Unix. The cat command allows you to concatenate and display the contents of multiple files. Here’s how you can use the cat command to merge log files: cat file1.log file2.log > merged_logs.log In the above command, file1.log and … Read more
To list the installed CPAN modules in Perl, you can use the following command: perl -MCPAN -e ‘my $c = CPAN::Shell->expand(“Module”, “/./”); print join “\n”, map { $_->id } sort { $a->id cmp $b->id } $c;’ This will list all the installed CPAN modules in alphabetical order. To search for a specific module, you can … Read more
To install Nmap on OpenBSD, you can use the package manager, pkg_add. Here’s the steps: Update the package repositories by running the following command: # pkg_add -u Install Nmap by running the following command: # pkg_add nmap Once the installation is complete, you can start using Nmap by typing “nmap” followed by the target host. … Read more
Installing VMware Guest Tools in a FreeBSD virtual machine involves the following steps: Download the appropriate VMware tools for your version of FreeBSD. Extract the tools archive to a directory of your choice. Open a terminal window in the directory where you extracted the tools. Mount the virtual machine’s disk image using the following command: … Read more
The “The search target requires INDEX-9. Please run make index or make fetchindex” error message in FreeBSD indicates that the necessary index for the ports collection is missing. This error occurs when you run a command such as “portmaster” or “portupgrade” without the necessary index. To resolve this error, run the following command as the … Read more