General Information
-------------------

To upgrade from a previous release simply follow the
installation instructions. Your configuration files will
not be touched. New options have the older behaviour as
default, if not set explicitely. I try to keep backward
compatibility forever.


To Version 2.5 or higher
------------------------

Upgrading to 2.5 or higher requires to first upgrade the
server. It can handle requests from older clients, but
newer clients fail on an older server.


To version 3.0 or higher
------------------------

The name of the service name changed from to afbackup
from backup (important for the entry in /etc/services).
Keep this in mind, when you are going to modify the
inetd's configuration.


Check your configuration for commands, that consist of
several subcommands separated by semicolons. It was no
problem in earlier versions, but is now crucial to make
sure, that these commands exit with a bad status (!= 0),
if one of the subcommands fails. Thus the subcommands
should be separated by && instead of the semicolon. This
does not always make sense. In some cases a good exit
status (0) must be enforced. In these cases you should
write:  <commands-that-might-fail>; exit 0


In some cases the server fails to run in buffering mode.
Why this happens, is actually unknown, but work is done
investigating this problem. In such a case error messages
show up for no obvious reasons. As a temporary solution
until the problem is fixed the server can be started with
the option -b. Add -b in the file /etc/inetd.conf after
the word afserver, so the whole line looks somewhat like
this:

afbackup stream tcp nowait backup /usr/backup/server/bin/afserver afserver -b /usr/backup/server/lib/backup.conf

Having successfully modified /etc/inetd.conf, send a
hangup signal to the inetd to activate the change. Find
out the PID typing   ps -uxa|grep inetd   and enter:
kill -HUP <PID>
with <PID> replaced by the real process id. The -b option
turns off buffering, so performance is worse, but until
the problem is fixed, there's no way around this, sorry.


If you make the backup into a filesystem instead of a
tape, check for the recommended settings of new parameters
in the HOWTO. The default might not be appropriate for
this configuration.


You might want to use DES encryption instead of the old
shuffeling algorithm. 128 Bit DES encryption can be used
now, what is actually and i think for the next 100 years
not crackable. Note, that whether using DES or not is a
compile time option and no runtime setting. Thus clients
and server must be compiled in the same manner. To get
the appropriate DES library, ask you next archie server
or altavista for libdes. The actual version by the time
of writing this is 3.23.


To version 3.1 or higher
------------------------

If using several backup servers for one client, the server
and port used for this client up to now should be the first
one supplied in the client side configuration. I.e. the
new entries should be appended to the existing ones for the
backup server hostname, port number and cartridge set number
(see: HOWTO Q9).
