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Raghbir_Sandhu's avatar
Raghbir_Sandhu
Icon for Altocumulus rankAltocumulus
Mar 30, 2021

AD Authentication Failing in APM

Following steps were taken. However, I am getting the error Common/devportal.kellogg.com_access_process:Common:eff7711c: AD module: authentication with 'testuser1' failed: Invalid format of Kerberos ...
BIG-IP Access Policy Manager (APM)
LTM
security
Nikoolayy1's avatar
Nikoolayy1
Icon for MVP rankMVP
Mar 30, 2021

Did the server team check that their AD server has the same time/clock values and also their logs? The issue will not always be the F5. Also check the hardware clock on the F5 device just in case:

 

https://support.f5.com/csp/article/K3381

 

 

 

Maybe also test if with LDAP there are no issue, you may use ldapsearch or adtest tool on F5 device as maybe the F5 is not telling us what is exact issue?

 

 

If someone has better idea, please also share it.

 

 

 

Also have you checked everything in :

 

 

https://support.f5.com/csp/article/K24065228

 

https://support.f5.com/csp/article/K40119818

  • Raghbir_Sandhu's avatar
    Raghbir_Sandhu
    Icon for Altocumulus rankAltocumulus
    Mar 30, 2021

    Thanks for the reply. I have check the HW and Systems time. They were different, however now HW and Systems time is with in 3 second. The other thing is, i am able to authenticate using LDAP AAA (not Active Directory). I used the same AD servers. But authentication failed with Active Directory AAA.

     

    One question I have, Can we use the AAAA LDAP authentication for Kerberos SSO with the Kerberos SSO profile.

     

    Any suggestion.

    • Nikoolayy1's avatar
      Nikoolayy1
      Icon for MVP rankMVP
      Mar 30, 2021

      Still better to ask also the server team to check their AD logs and so on. See this "Table 3.1 Client-side and server-side authentication method support matrix" on the link below:

       

      https://support.f5.com/csp/article/K08200035#link_02

       

       

      Basically on the F5 device you use for the client side authentication the apm web form (webtop) or HTTP Basic and the server side authentication (SSO) can be KERBEROS.

       

       

       

    • Raghbir_Sandhu's avatar
      Raghbir_Sandhu
      Icon for Altocumulus rankAltocumulus
      Apr 01, 2021

      I am able to solve the issue. In the krb5.conf file, there was a extra space in the ticket_lifetime = 24 parameter setting. I removed the extra space and now it is working.