NW SSO 2.0 With Kerberos only authentication fails sporadically

Hi,

We have configured kerberos only authentication (NW SSO) for all our SAP systems. The single sign-on works perfectly fine. But in our production systems there are 9 app servers. We have activated SNC as per procedure and we use logon groups for signing in to SAP. The SSO works fine, but sporadically it does not work and it prompts for user name and password in the login screen.We have tested SSO for each individual app servers including CI and it works fine. Even with logon groups it works fine most of the times but at times it prompts for login screen. We use Secure Login client 2.0 SP3.

Thanks

Thilip Kumar