pioctl (path-based ioctl) calls are used by various tools to communicate with the AFS Client Service. Some of the operations performed include:
setting/querying tokens (tokens.exe, aklog.exe, afscreds.exe)
setting/querying ACLs
setting/querying cache parameters
flushing files or volumes
setting/querying server preferences
querying path location
checking the status of servers and volumes
setting/querying the sysname list
pioctl calls are implemented by writing to a special UNC path that is processed by the AFS Client Service. If there is a failure to communicate with the AFS Client Service via SMB/CIFS, it will be impossible to perform any of the above operations.
To assist in debugging these problems, the registry value:
[HKLM\SOFTWARE\OpenAFS\Client]
REG_DWORD: IoctlDebug = 0x01
should be set. Then any of the commands that perform pioctl calls should be executed from the command prompt. With this key set the pioctl library will generate debugging output to stderr. The output will contain the Win32 API calls executed along with their most important parameters and their return code. The MSDN Library and the Microsoft KnowledgeBase can be used as a reference to help you determine the configuration probem with your system.