TOTPRadius can be used as an LDAP Proxy, or to be more correct, RADIUS to LDAP Proxy. In this configuration, the user authentication is done against 2 sources: the password is verified by the upstream LDAP server(s), and the OTP is checked by the TOTPRadius itself locally. In some use cases, there is a need to exceptionally allow using a single factor authentication against TOTPRadius. This may be needed to provide access to system or other generic accounts used, for instance, in automated scripts, where the second factor is not possible to be entered.

To address this issue, you can use one of the following options.

User level setting

You can set this behavior at the user level, but changing the 'Allow single factor' value to 'Enabled'

This will allow this particular user to log in using LDAP Password + OTP, OTP only, or LDAP Password only.
Please note that the LDAP Password only option will work for TOTPRadius v 0.2.7 or newer.

Subnet level 

Starting from TOTPRadius v0.2.9, it is also possible to allow single factor logins from a trusted IP range. This setting is called 'Trusted IP Configuration' and can be set in the Settings → Advanced Settings section.

The value is expected in CIDR format. To disable this functionality, set the value of this field to 'none'.