[email] forward file not working

the solution (alternative) : set new alias and apply new setting.

ref: http://thepoch.com/tumblr/set-up-your-server-to-forward-root-emails-to-an.html

First, you edit /etc/aliases. On our CentOS 6.2 systems, it's the last line that's important. By default it's:

# Person who should get root's mail
#root:      marc

It's commented out, and set to forward to "marc". So, uncomment it by removing the "#" character in front of root. Then change "marc" to an email address you want to receive notifications. So now, it should look something like this:

# Person who should get root's mail
root:       notifications@example.com

Save the file. Now, in order for sendmail (or in CentOS 6.2's case, postfix) to see the new alias, you have to run the following in your terminal:

newaliases

If there's no output, then it should have worked.