Duo has been restored and multi-factor authentication reenabled.
Update, Jan 15, 2019 — Duo has posted their postmortem report for the incident.
Update, 4:27 p.m. — This issue has been resolved. Multi-factor authentication has been reenabled, and Duo is now back to normal operation. We apologize for any inconvenience this may have caused. If you’re still experiencing issues with this service, please contact the IT Support Center at (310) 825-8000 or email@example.com.
Update, 1:20 p.m. — As a workaround, MFA has been put in bypass mode and is not being required for Shibboleth currently.
12:40 p.m. — We’re getting reports that Duo users may be experiencing issues with slow or nonresponsive authentication. The issue began at 12:40 p.m. We are working closely with Duo to get this issue resolved as soon as possible. We’ll send out another update when we have more information from Duo. Thanks for your patience.
You can also check Duo's status page.
If you’re one of the affected users, or would like more details, please contact us at (310) 825-8000 or firstname.lastname@example.org.