[569] in Info-AFS_Redistribution
Changing cell configurations
daemon@ATHENA.MIT.EDU (Stig Ostholm)
Tue Feb 4 05:56:35 1992
Date: Tue, 4 Feb 92 09:38:10 GMT
From: Stig Ostholm <ostholm@ce.chalmers.se>
To: info-afs@transarc.com
A browse through the afs kernel code to pinpoint the problem with calls
to a non-existing server/cell has given the following results:
In the function `afs_NewCell':
1) A cell can not be deleted from the cache manager structures,
only changed. The only way to modify a cell is through the
AFSOP_ADDCELL call wich require at least one database server.
2) "Old" database servers are still present in the cache manager
structures after an AFSOP_ADDCELL call is made for an existing
cell with a list of new database server. The array `cellHost'
of pointers to db servers is simply cleared and the new db servers
are inserted. An old db server is still present in the `afs_servers'
structure and points back to its former cell.
If these observations are correct, could that be cause for the problem with
clients trying to contact non-existing (removed) servers?
Something like an afs call AFSOP_DELCELL that deletes all information about
a cell from the cache manager should be added.
All information about old database servers and all volume/server information
for a deleted cell should be removed from the cache manager.
We would like to know how non-DCE system are going to handle the information
about cells/db-servers in the future. The current solution with a static text
file containg all information has the same inconsistency problems as the host
file before DNS.
_
Stig Ostholm & Hakan Torbjar
Chalmers University of Technology
