In this post, we will explain how to check the md5sum value on Linux distributions, using the Terminal.
What is MD5 and why should be validated ?
When you download the ISO file, for example (whether an operating system or program or any other file) it is advisable to test its health, safety and file security, lest there be damaged or corrupted, in this case it's called MD5 Test or hash value (retail), which is about mathematical equation consists of a set of numbers and letters, and the way to verify the equality of the value of the real hash to the given party publisher with the value of the ISO file that is loaded; the higher the ISO file size the greater the need for a testing process to avoid errors during use.
There are some different software in the Linux system to verify the integrity of the file and is known to many, but in here we will test the validity through the Terminal, without the need for programs.
1. Open the terminal Ctrl + Alt + T and paste the following command :
Downloads must be replaced with the name of the folder in which the file to check is allocated in.
2. paste the following command :
Replace ubuntu-11.10-dvd-i386.iso with the desired file.
3. The following result will appear, note that you have produced a hash value :
4. Now you should check matching the number that publisher gave you, with the number that resulted in the terminal, the correspondence with each other, the safe the file is, but if they have not corresponded you must re-download the file again.
5. That's it.