Skip to Content
Jul 28, 2016 at 10:30 AM

Best ways to migrate from XYZ-SNC to SAP SSO 3.0 SNC library


Hi Experts,

would love to have a discussion with you about the best way to move from XYZ-SNC library (such as MIT kerberos) to SAP SSO 3.0. Lets assume a customer has a large environment and already SNC in use based on a 3rd Party Kerberos library. Now he wants to move to SSO 3.0 to make use of all the nice features, such as parallel operation of SNC with X.509 and Kerberos and many other benefits of using a officially supported and certified SNC library.


  • As of today SAP AS ABAP are operated with any SNC Kerberos Library (or could be X.509 also)
  • A migration to SAP Single Sign-On 3.0 solution is now being considered


  • The parallel operation of multiple SNC libraries on a SAP AS ABAP is not possible
  • The parallel operation of multiple SNC libraries on the client side is not possible (maybe possible)
  • Although SNC libraries are based on the standard interface GSS-API V2, the token formats may be incompatible, this will impact the user mapping format (different canonical name format for the SNC-Name).
  • With an exchange of the SNC Library all SNC-Names in the user master data SU01 (Table USRACL) must be re-calculated and generated (Update of the User Mapping)
  • Different format/syntax for the snc/identity/as impacting the client rollout (saplogon.ini)
  • Often all SAP users don’t have any active passwords or they simply don’t know their passwords anymore because of using SSO :-)
  • Looks like it is required to switch back to Username + Password based authentication during a migration phase on a per Server basis
  • In short, a migration seems to be impossible without either big-bang or switching back to password auth (losing SNC security)
  • RFC connections between systems may be in use and must be considered for the migration

What could help?

The parallel operation of two SNC libraries on the client side (smells like a feature request)

I would love to have a “standard” way (at least on the SAP Logon/GUI) where a user (or the admins) are able to “control” which SNC library is used for which connection. Using SAPGUI.EXE allows to specify a parameter for SNC_LIB, that may help, haven't tried it yet. But just a small improvement on the SAP GUI client, an additional saplogon.ini parameter or whatever which overrules the SNC_LIB variable would help. A place where you would be able to define the full path and SNC lib used for a specific connection.

This could allow the use of two SNC solutions on one Windows client in parallel. That would provide customers with the possibility, to rollout the SAP Secure Login Client (SLC) in addition to an existing SNC client installation and migrate the ABAP backends one after another. Connections to migrated servers would use the new SAP CommonCryptoLib via SLC while the old SNC based connections would still work. This approach could be controlled by the IT organization using a phased approach for the migration. Do you have additional thoughts and ideas?

Lets discuss.