.TH PAM_GOOGLE_AUTHENTICATOR 8 "25 Feb 2011" .\" disable hyphenation .nh .SH NAME pam_google_authenticator \- PAM module for two-step verification .SH SYNOPSIS .B pam_google_authenticator.so .SH CAVEATS The current version requires the existance of ~/.google\-authenticator. If the file does not exist for a user, the authentication module will fail. Each user MUST create their secret key with google\-authenticator(1) PRIOR TO enabling this module. When used with sshd remember to edit sshd_config: ChallengeResponseAuthentication yes .SH EXAMPLES Add this line to /etc/pam.d/: auth required pam_google_authenticator.so If needed only for a certain group: auth [default=1 success=ignore] pam_succeed_if.so quiet user ingroup auth required pam_google_authenticator.so .SH "SEE ALSO" google-authenticator(1) http://code.google.com/p/google-authenticator/ /wiki/PamModuleInstructions