OpenAFS CVS Commit: openafs/src/WINNT/afsd by jaltman

Wed, 26 Dec 2007 11:22:20 EST

Update of /cvs/openafs/src/WINNT/afsd
In directory GRAND.CENTRAL.ORG:/home/jaltman/openafs/cvs-1-5/src/WINNT/afsd

Modified Files:
      Tag: openafs-devel-1_5_x
	cm_callback.c cm_cell.c 
Log Message:
DELTA DEVEL15-windows-callback-restore-multi-cell-servers-20071226

The case of and is a hideous abuse of
the AFS cell name space.  There are many negatives associated with
trying to support two different cell names pointing at overlapping
vlserver lists:

(1) The CM can store duplicate entries for all of the data simply because
    the cell name that was used is different

(2) If the CM attempts to optimize the data storage by aliasing or otherwise
    combining the cell names as part of one cm_cell_t object, then future
    attempts to separate the two cell names will require the destruction
    of the cache.

(3) If the CM does not associate a callback revoke with a particular cell,
    then the status data associated with any entry that matches the revoked
    AFSFid will be discarded.  For volume callbacks this can have a serious
    impact because volume IDs are not unique across cells and discarding
    status data for readonly volumes that are in use can result in a
    significant number of FetchStatus requests being sent to the associated
    file server.

There are other issues as well involving authentication.

The case of advertising the vlserver addresses of should be considered a hack; a hack that the Windows
client will no longer ensure will work.

Additional debugging messages have been added to assist individuals attempting
to debug why callback revokes do not appear to take affect when two cell
names share the same vlserver data.

--- DELTA config for openafs-devel-1_5_x follows ---
DEVEL15-windows-callback-restore-multi-cell-servers-20071226 openafs/src/WINNT/afsd/cm_callback.c
DEVEL15-windows-callback-restore-multi-cell-servers-20071226 openafs/src/WINNT/afsd/cm_cell.c