Duo 2FA for SSH to Ubuntu Server

In this demonstration, we will configure Duo two-factor authentication for Ubuntu servers. Lab Set-up Ubuntu Server 18.04.4 (Bionic)Duo account Add Local User Accounts If you have multiple user accounts that require access to the servers, create these users before adding…

Duo KB: Error starting userland proxy: listen tcp4 0.0.0.0:53: bind: address already in use

Problem While configuring the Duo Network Gateway (DNG) on a Ubuntu device for RDP, I came across the following error while trying to configure a DNS service: The error is presented because the Ubuntu system is using the UDP port…