The kernel patch for Oracle Enterprise Linux Unbreakable Enterprise Kernel version 2.6.39-400.245.1.el5uek causes authentication with Authentication Services to fail.
A vastool flush command may contain errors like this one.
ERROR: Error receiving IPC buffer from server: Invalid argument
ERROR: Failed to send/recv DomainInfo Flush IPC request, payload_err=22
ERROR: Failed to send domainsids flush IPC, error=22
A change in the most recent version of this patch is now causing flushes and authentication to fail.
Oracle has logged a defect number for this issue as 2004916.
This issue has been resolved in version 2.6.39-400.250.5 and higher. It is now publically available for download and installation.