Configure Cisco ASA IKEv2 VPN

Okta lets you manage authorization and access to on-premises applications and resources using the RADIUS protocol and the Okta RADIUS agent. With the Okta RADIUS Server Agent organizations can delegate authentication to Okta. This page describes how to configure Cisco ASA IKEV2 VPN to use EAP-TTLS and the Okta RADIUS Server Agent.

If you are using AnyConnect v4.4 and greater and ASA version 9.7.1 and greater consider using SAML.

Topics

Before you begin

Meet the following network connectivity requirements before you install the Okta RADIUS agent:

Source Destination Port/Protocol Description
Okta RADIUS Agent Okta Identity Cloud TCP/443

HTTP

 Configuration and authentication traffic.
Client Gateway Okta RADIUS Agent UDP/1812 RADIUS (Default, you can change this when you install and configure the RADIUS app) RADIUS traffic between the gateway (client) and the RADIUS agent (server).

Supported factors

The size of the challenge message can be too large for the RADIUS prompt if you let users enroll too many factors. Okta recommends that you enroll no more than eight factors at a given time.

Okta supports the following factors for RADIUS apps:

MFA Factor

 Password Authentication Protocol (PAP) Extensible Authentication Protocol - Generic Token Card (EAP-GTC) Extensible Authentication Protocol - Tunneled Transport Layer Security (EAP-TTLS)*
Custom TOTP Authentication Supported Supported Supported - as long as challenge is avoided.
For example MFA only or "Password, passcode".
Duo (Push, SMS, and Passcode only) Supported Supported Duo passcode only.

Email

Supported

Supported

Supported when the string "EMAIL" is initially sent.
Refer to associated note.

Google Authenticator

Supported Supported Supported, as long as challenge is avoided.
For example MFA only or "Password, passcode".

Okta Verify (TOTP and PUSH)

Supported Supported Supported as long as challenge is avoided.

For example: MFA-only or "Password, MFA" for TOTP. Push can work with primary authentication with MFA as the push challenge is sent out-of-band.

Okta Verify (number challenge)

Not supported

Not supported

Not supported

RSA Token/ On-prem MFA

Supported

Supported

Supported - as long as challenge is avoided.
For example MFA only or "Password, passcode".

Security Question

Supported (Password and MFA only) Supported (Password + MFA only).
 Not supported
SMS authentication Supported Supported
Supported when the string "SMS" is sent.
Refer to associated note.
Symantec VIP Supported Supported Supported - as long as challenge is avoided.
For example MFA only or "Password, passcode".

Voice Call

Supported Supported Supported when the string "CALL" is sent.
Refer to associated note.

YubiKey

Supported Supported Supported - as long as challenge is avoided.
For example MFA only or "Password, passcode".

* RADIUS supports three authentication methods:

  • Password + MFA: Primary authentication using password, then the user is prompted to select factors to complete the authentication.
  • MFA Only: Instead of password, users enter either a one-time passcode (OTP), or one of EMAIL, SMS, CALL, PUSH (case insensitive).
  • Password and Passcode: Password entered immediately followed by a passcode in a request.
    Must be in the same request, for example: Abcd1234,879890" or "Abcd1234,SmS".

Protocols support the following authentication methods:

Protocol Supports
PAP Password and MFA, MFA, "Password and passcode".
EAP-TTLS MFA only, "Password and passcode".
EAP-GTC Password and MFA, MFA only, "Password and passcode".

Users must send the specified string EMAIL/SMS/CALL, which initially returns a failure. This results in the generation of an OTP provided using the specified method. The provided OTP can then be used for authentication.

EAP-TTLS doesn't support enrollment

Authentication will fail unexpectedly when EAP-TTLS is enabled, either Okta Verify or Phone are specified as the required enrollment policy, and the user isn't enrolled in that factor.

U2F Security and Windows Hello aren't compatible with RADIUS-enabled implementations. See RADIUS applications in Okta and About multifactor authentication.

Passwordless authentication

RADIUS authentication uses passwords as the primary authentication mechanism. Traditional RADIUS authentication can't be performed with passwordless users. RADIUS can use other factors for authentication when the application setting property Okta performs primary authentication is cleared. See 2FA Only (Passwordless Mode) in RADIUS applications in Okta for addition detail.

Typical workflow

Task

Description
Download the RADIUS agent
Install the Okta RADIUS Agent.
  • Install either the Windows or Linux RADIUS agents as appropriate for your environment.
Configure the app
Configure gateway
Configure optional settings
Configure Windows VPN
Add root CA
Test

Related topics