[67] in Athena_Backup_System
ADSTAR backup system
daemon@ATHENA.MIT.EDU (Richard Basch)
Wed Jan 25 14:51:20 1995
Date: Wed, 25 Jan 1995 14:50:33 -0500
To: athena-backup@MIT.EDU
From: "Richard Basch" <basch@MIT.EDU>
I briefly glanced at the ADSTAR backup documentation.
1. It appears to have no client-server authentication.
(This is not good.)
2. It appears that it attempts to backup at a file level.
This is not appropriate for AFS.
By file backups will have the following problems:
1. It is much slower, as you have to go through the client's cache and
server processing per file.
2. It does not preserve volume structure.
They made references to AFS paths, and backing up ACL information,
but there were no references to backing up volume structure.
3. It will not ensure stable backups, as it makes no reference of
busying out the volumes during the backup (and if it does do it
at a file-level through the fileserver, there is no way it can).
4. At a per-file backup level, it will require that all the directories
be available to some entity. This will require changing EVERY acl
in the Athena cell, and all other cells that we wish to backup.
If a user removes this entity from the acl, his files will not
be backed up.
As such, the ADSTAR backup system would probably require substantial
internal rework to provide a modular interface by which multiple
filesystem types can be completely backed up, as they exist. AFS looks
like it was an after-thought in this design.
-Richard
