Flux and other ARC-TS resources require two-factor authentication with both a UMICH password and Duo (which replaces MTokens starting July 20, 2016) in order to log in.
Duo provides several options, including a smartphone or tablet app, phone calls to landlines or cell phones, and text messages. Instructions on enrolling in Duo are available at http://its.umich.edu/two-factor-authentication.
Using your two-factor key to login
The following is an example of what opening a session on Flux might look like.
$ ssh flux-login Password: Duo two-factor login for uniqname Enter a passcode or select one of the following options: 1. Duo Push to XXX-XXX-1810 2. Phone call to XXX-XXX-1810 3. SMS passcodes to XXX-XXX-1810 Passcode or option (1-3): 1 Success. Logging you in... uniqname@flux-login ~$
If you need help go to the U-M Duo page, contact 4help@umich.edu, or call (734) 764-4357 (764-HELP). Questions on the Flux cluster or other ARC-TS resources can be directed to hpc-support@umich.edu.