John the Ripper cracking passwords

To crack passwords using John the Ripper first we need to install it with the following script:

#/bin/bash
# Centos 7 John the Ripper Installation
yum -y install wget gpgme
yum -y group install "Development Tools"
cd
wget http://www.openwall.com/john/j/john-1.8.0.tar.xz
wget http://www.openwall.com/john/j/john-1.8.0.tar.xz.sign
wget http://www.openwall.com/signatures/openwall-signatures.asc
gpg --import openwall-signatures.asc
gpg --verify john-1.8.0.tar.xz.sign
tar xvfJ john-1.8.0.tar.xz
cd john-1.8.0/src
make clean linux-x86-64
cd ../run/
./john --test
#password dictionnary download
wget -O - http://mirrors.kernel.org/openwall/wordlists/all.gz | gunzip -c > openwall.dico

Then we execute ./john-1.8.0/run/john -wordlist:openwall.dico passfile.txt

And we wait for the passwords to be cracked.