FortiGate
FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
adimailig
Staff & Editor
Staff & Editor
Article Id 389947
Description This article discusses how Authentication Keepalive is causing IPsec VPN with SAML Authentication to fail.
Scope FortiGate.
Solution

When enabling Authentication KeepAlive causes the IPsec VPN with SAML not to connect.
After the end user enters the Single-Sign-On credential for SAML, FortiClient responds with 'IPSec Connection is down' or directly brings back to the 'Connect' page.


Debug commands for IPsec troubleshooting (Technical Tip: Troubleshoot IPsec SAML Dial UP tunnel) show that traffic stops after FortiGate sends the Authentication Keepalive Portal. N
o IKE negotiation is initiated between FortiGate and the end user.


Sample Log:

FortiClient initiated SAML authentication:

[authd_local_saml_auth:5778]: SAML login with UID '2D56XXXXXXXXXXX30A4D3DA0E'.
[authd_http_prepare_javascript_redir:3942]: https://54.252.41.X:9443/saml?070c028b958de7bd

End user provided SSO/SAML credentials, which were received by FortiGate.

samld_send_common_reply [95]: Attr: 10, 43, 'username' 'adimailig@fortinet-us.com'
samld_send_common_reply [95]: Attr: 10, 51, 'group' '014XXXXX-XXXX-XXXX-XXXX-XXXXX9a'
<>
[authd_http_on_saml_msg:4612]: user 'adimailig@fortinet-us.com'.
[authd_http_on_saml_msg:4604]: group '014XXXXX-XXXX-XXXX-XXXX-XXXXX9a'.


KeepAlive Portal is sent by FortiGate to FortiClient, and the connection stops. IKE negotiation not initiated.

[authd_http_prepare_javascript_redir:3942]: https://54.252.41.X:9443/keepalive?07060802060e090d
<>

[132] __saml_auth_cache_push-Auth cache created, user='2D56XXXXXXXXXXX30A4D3DA0E', SAML_server='IPSEC_SAML', vfid=0
[139] __saml_auth_cache_push-Hash bucket 198
[186] __saml_auth_cache_push-New auth cache entry is created, user='2D56XXXXXXXXXXX30A4D3DA0E', saml_user='adimailig@fortinet-us.com', expires=1746003434, SAML_server='IPSEC_SAML', vfid=0


This issue has been resolved in v7.6.4.

Workaround:
Disable Authentication KeepAlive to connect to the IPSEC VPN with SAML.

 

config system global

    set auth-keepalive disable

end


Related articles:
Technical Tip: Troubleshoot IPsec SAML Dial UP tunnel 
Technical Tip: Authentication keepalive page

Technical Tip: How to read SAML Debug output