The formatting of a hard disk partition on Linux is not very difficult if you use the right command. The mkfs command is used on Linux for this task; I will be showing a simple example of its usage here to make it clear how this is done. This is a simple example; I am … Read more
This is an example where I am using the rsync command to copy files from one computer to another. homer@deusexmachina ~ $ rsync -avz -e "ssh -p 443" [email protected]:/home/homer/Desktop/ /home/homer/Videos The authenticity of host ‘[192.168.100.4]:443 ([192.168.100.4]:443)’ can’t be established. ECDSA key fingerprint is ############################################. Are you sure you want to continue connecting (yes/no)? yes Warning: … Read more
There are many useful Linux tips that make the life of a Linux user much easier. One is for the VI or VIM editor. To open a file at a specific line; use this command. homer@deusexmachina ~/Documents/yadex-1.7.901 $ vim src/x11.h +33homer@deusexmachina ~/Documents/yadex-1.7.901 $ vim src/x11.h +33 This will open the file x11.h at line 33. … Read more
The touch command ordinarily does not allow the user to create files with a filename like –rf, but if you want to really annoy someone then you may use this command to create one. homer@debian:~$ touch — ‘–rf ‘homer@debian:~$ touch — ‘–rf ‘ And now you have a file named –rf. -rw-r–r– 1 homer homer … Read more
The bash shell allows the user to redirect output from one application to another or to a file. This is very useful when you are building a one liner script to perform a certain action. Here is a simple redirection. ls > ls.outls > ls.out This redirects the output of the ls command to a … Read more
The update-grub command will update the grub menu on Kali Linux. root@kali:~# update-grub Generating grub.cfg … Found background image: /usr/share/images/desktop-base/desktop-grub.png Found linux image: /boot/vmlinuz-3.12-kali1-amd64 Found initrd image: /boot/initrd.img-3.12-kali1-amd64 Found memtest86+ image: /boot/memtest86+.bin Found memtest86+ multiboot image: /boot/memtest86+_multiboot.bin No volume groups found doneroot@kali:~# update-grub Generating grub.cfg … Found background image: /usr/share/images/desktop-base/desktop-grub.png Found linux image: /boot/vmlinuz-3.12-kali1-amd64 Found … Read more
Change the default Plymouth theme on Ubuntu Changing the default plymouth theme on Ubuntu 14.10 is not very difficult. Just type this at the shell prompt. This will set the new theme. root@homer-eME730:~# update-alternatives –install /lib/plymouth/themes/default.plymouth default.plymouth /lib/plymouth/themes/ubuntustudio-logo/ubuntustudio-logo.plymouth 100root@homer-eME730:~# update-alternatives –install /lib/plymouth/themes/default.plymouth default.plymouth /lib/plymouth/themes/ubuntustudio-logo/ubuntustudio-logo.plymouth 100 Now we need to save our changes. root@homer-eME730:~# update-alternatives –config … Read more
The mount command shows information about your mounted partitions on your machine. iMac305:~ admin$ mount /dev/disk0s2 on / (hfs, local, journaled) devfs on /dev (devfs, local, nobrowse) map -hosts on /net (autofs, nosuid, automounted, nobrowse) map auto_home on /home (autofs, automounted, nobrowse) map -fstab on /Network/Servers (autofs, automounted, nobrowse) /dev/disk0s3 on /Volumes/Scratch (hfs, local, journaled)iMac305:~ … Read more
This is a system information script I am working on. This shows some useful information about your Linux system. #!/bin/bash echo " My System information script." echo " " echo " " echo "The computer has: $(awk < /proc/meminfo ‘{ if ($1 == "MemTotal:") { print $2 }}’) Kilobytes of RAM." echo "The … Read more
This command will get the IP address from the interface supplied and then ping it. ping $(ifconfig enp6s1 | awk ‘/inet / { print $2 } ‘ | sed -e s/addr://)ping $(ifconfig enp6s1 | awk ‘/inet / { print $2 } ‘ | sed -e s/addr://) Here is an example. This shows how well this … Read more
This is a very strange shell trick that allows you to have a set of parameters to a Linux command that are separated by single quotes. [homer@localhost ~]$ df -h’l’a’T’ Filesystem Type Size Used Avail Use% Mounted on rootfs rootfs 216G 75G 130G 37% / proc proc 0 0 0 – /proc sysfs sysfs 0 … Read more
The iptables -L or iptables –list commands will list all of the iptables rules that are set on your Linux machine. Below is the abbreviated output of this command on my Fedora Linux system. [root@localhost homer]# iptables –list Chain INPUT (policy ACCEPT) target prot opt source destination ACCEPT all — anywhere anywhere ctstate RELATED,ESTABLISHED ACCEPT … Read more
The tar command on Linux is very useful for uncompressing files on your Linux machine. The most used command on a Linux system is uncompressing files that you have downloaded from an Internet source. The tar -xvf command will uncompress a tar.gz file. ~$ tar -xvf myfile.tar.gz~$ tar -xvf myfile.tar.gz To uncompress a tar.bz2 file … Read more
This simple one liner will print out your IP address and then IPv6 equivalent if you have it set. [homer@localhost ~]$ ifconfig enp6s1 | awk ‘/inet/ { print $2 } ‘ | sed -e s/addr:// 192.168.1.2 fe80::213:46ff:fe3a:283[homer@localhost ~]$ ifconfig enp6s1 | awk ‘/inet/ { print $2 } ‘ | sed -e s/addr:// 192.168.1.2 fe80::213:46ff:fe3a:283 Here … Read more
Linux hardware information commands. There are many commands available for Linux that allow the user to get information about their hardware. Here is a handful of them. The lshw command is very useful for getting information about your installed hardware. ubuntu ~ $ sudo lshw -short H/W path Device Class Description ============================================================================================================================================== system HVM domU … Read more
The md5sum command on Linux is used to get a number that is the checksum of the file. This is commonly used to verify downloaded files to check that the file has not been modified. Below is an example, the md5sum command is used on a BMP file and I get the file checksum output … Read more
The sed command is very useful for searching and replacing text in a file. This is how to search for and replace a text string in a file. Homer@bejiitas ~ $ sed -i ‘s/<main>/<mein>/gi;’ my.cHomer@bejiitas ~ $ sed -i ‘s/<main>/<mein>/gi;’ my.c This is how to search and replace text in a file and leave a … Read more
I am having a quick look at the Macintosh OSX desktop on an Apple Macintosh computer and the interface is very annoying indeed. The Finder does find files; but most of the results are not what you were looking for. And to take a screenshot you have to use quite a complex combination of keys … Read more
How to add a user to the sudoers file to allow them to use the sudo command. The /etc/sudoers file contains definitions of all the users that are allowed to use superuser privileges on Linux to perform various tasks as an administrator. This is how to add a user to this file to allow them … Read more
In this example; I am using the -i parameter to the rm command to ask for permission before erasing a file. This is very useful if you want to be sure that you are wiping the correct file. homer@deep-thought ~/Documents $ rm -i thoughts.txt rm: remove regular file ‘thoughts.txt’? yhomer@deep-thought ~/Documents $ rm -i thoughts.txt … Read more