If the user doesn’t have a password set or your just tired of being prompted everytime you use sudo, heres the solution.
Edit the line that defines the group/user in the sudoers file to look like this (more here):
username ALL=(ALL) NOPASSWD: ALL
This might be nice if your are using only public/private keys for your users and so a:
passwd -l username
can be used to disable/lock the users’ password (this only means they can’t possibly use a password to login, it does not mean they can’t log in).
If this stands the case for all ssh logins, you can also ensure:
is defined in your sshd_config. Security br0. It’s awesome.
PS: In Gentoo, and I think OSX, it seems the sudoers file has the “wheel” group already setup with a NOPASSWD, making your only task to add your user to that grp through a:
usermod -G wheel username