How to replace, add word or information in a file with vi editor

 How to replace, add word or information in a file with vi editor

If you need to add a new server for example after test and it is called energia
# vi test
Argentina rock=test,energia
Venezuela rock=test,energia,test1
Colombia  rock=test,energia,test1,test2
~
~
:%s/rock=test/rock=test,energia/g

Or if you want to replace root for another word for example rock

Argentina root=test,energia
Venezuela root=test,energia,test1
Colombia  root=test,energia,test1,test2
~
~
~
~
:%s/root/rock/g

You have other form to do it, however it is the simple way to perform some change in any files, for example /etc/dfs/dfstab or in the vfstab when you need to change a specific word in any file

Regards
Roger