Search for blog posts, documentation, or pages

We’ve open-sourced our duo_unix package for easy, drop-in two-factor authentication to any Unix system. Combined with our hosted service, it’s the simplest way to protect logins to your cloud or datacenter hosts with strong, out-of-band authentication. Here’s how:

1. Set up your Duo account

First, create your new Duo account at duosecurity.com – it’s free for up to 10 users or for any open-source project!

In the Duo admin interface, create a new Unix integration for your host:

newintegration.png

You’ll need the resulting integration and secret keys for your duo_unix configuration:

integration.png

2. Set up login_duo on your Unix system

Next, on your Unix system, download, build and install the duo_unix distribution (or install the appropriate package for your OS: Debian, Ubuntu, etc.):

build.png

Once installed, edit /etc/duo/login_duo.conf as root to add your integration and secret keys:

conf.png

Then as a regular user, test login_duo manually. If everything’s set up correctly, you’ll be prompted to enroll (or check your syslog for errors):

enroll.png

Enroll your phone:

enroll.png

The next time you run login_duo, you’ll be prompted to authenticate with your phone:

authprompt.png

3. Enable login_duo on your Unix system

To enable Duo login for individual accounts using SSH pubkeys, use the authorized_keys command option. For example, to verify individual admins authorized to log into a shared root account:

root_duo.png

* This also works for user-local installations (e.g. $HOME/bin) without root access in shared web hosting environments — just specify the location of login_duo.conf with -c.

Similarly, you can enable Duo login system-wide to follow any SSH login method (password, pubkey, etc.) for any user. Edit your /etc/sshd_config (or /etc/ssh/sshd_config) to add the following line:

ForceCommand /usr/local/sbin/login_duo

And optionally limit Duo login to a subset of users by UID or group in /etc/duo/login_duo.conf:

group = wheel

The duo_unix PAM configuration is similar if you’d like to protect other PAM-enabled daemons or programs (e.g. sudo).

Let us know if you have any questions or comments!

Dug Song
CEO & Co-Founder

Dug has a history of leading successful products and companies to solve pressing security problems. Dug spent 7 years as founding Chief Security Architect at Arbor Networks, protecting 80% of the world’s Internet service providers, and growing to $120M+ annual revenue before its acquisition by Danaher. Before Arbor, Dug built the first commercial network anomaly detection system (acquired by NFR / Check Point), and managed security in the world’s largest production Kerberos environment (University of Michigan).

Categories

Free Guide

Duo Securitys Guide to Securing Patient Data

With a significant rise in healthcare-related criminal attacks, the need for a new approach to securing patient data is greater than ever.

Tags

phishing (18)  security news (17)  two-factor-authentication (15)  healthcare security (15)  passwords (14)  weekly ink (13)  federal cybersecurity (10)  malware (9)  infosec-evolution (9)  cloud security (9)  retail data breaches (8)  rsac2015 (8)  banking security (8)  duo mobile (7)  stolen-passwords (6)  2fa (6)  financial data breach (6)  financial institutions (6)  data breaches (6)  pci dss (6)  ooba (6)  atms (5)  webinar (5)  encryption (5)  stolen credentials (5)  transaction-level 2fa (5)  financial data security (4)  pos malware (4)  medical identity theft (4)  healthcare cybersecurity (4)  remote access security (4)  bank security (4)  data breach notification (4)  vulnerability (4)  hipaa (4)  third-party security (4)  retail data security (4)  mobile security (4)  retail (4)  healthit (4)  anthem (3)  iot security (3)  defense in depth (3)  security threats (3)  uk security (3)  dyre trojan (3)  rig exploit kit (3)  otp bypass (3)  payment card breach (3)  media security (3)  critical infrastructure security (3)  law firm security (3)  ffiec (3)  twitter (3)  remote access attacks (3)  retail data risks (3)  ssl (3)  manufacturing security (3)  retail ebook (3)  strong-authentication (3)  target (3)  platform edition (3)  health it (3)  two-factor (3)  home depot (3)  e-prescriptions (3)  hipaa security rule (3)  google (3)  higher education (3) 

Duo is hiring!

View our open positions

Subscribe to our Newsletter

Get product updates, interesting content, and invitations to online and live events.