Selenium installation in Centos 7.X:

# mkdir -p /opt/selenium/2.53
# chown -R <username> /opt/selenium/

# su - <username>
$ cd /opt/selenium/2.53

$ wget http://selenium-release.storage.googleapis.com/2.53/selenium-server-standalone-2.53.0.jar
$ ln -s /opt/selenium/2.53/selenium-server-standalone-2.53.0.jar /opt/selenium/selenium

 $ java -jar /opt/selenium/selenium