Copying and pasting an existing cifs fstab entry, using a credentials file, failed on a system upgraded from Centos 5 to Centos 7. Turns out the syntax for the username and domain in the credentials has changed.
Old syntax for the credentials file was...
username=MYDOMAIN\myuser
password=supersecretpassword
New syntax is...
username=myuser
domain=MYDOMAIN
password=supersecretpassword
This also applies to the command line. Old syntax for the command line was...
mount -t cifs //myserver/myshare /mountpoint -o username=MYDOMAIN/myuser,password=supersecretpassword
New syntax for the command line is...
mount -t cifs //myserver/myshare /mountpoint -o username=myuser,domain=MYDOMAIN,password=supersecretpassword
