"John R. Jackson" wrote:
>
> >You understand a chance as a curse: AMANDA _has_ the qualities to become
> >a real, integrative, superlative backup tool. ...
>
> So explain to me exactly what you think Amanda should do to solve this.
> And keep in mind that the design philosophy is that it uses other tools
> and that it does **not** do the work itself.
Separate "estimator programs" from "backup programs". As it is now, if I
decide to use tar for my backups, it will also be used for the
estimation phase (which is where my problem is: estimation of
incrementals). But tar may not be estimating correctly in my case,
although it may be perfect in backing up.
So the idea is to give us the chance to write our own "estimator
function": a script that gets a filename, a date and/or a backup level
(and perhaps also other parameters) as input and gives a boolean as
output ("yes, it should be backed up" or "no, it shouldn't"). This
script will have a "default" code in it: if tar is used, then tar is
invoked to determine if the file should be backed up, if dump is used,
then dump is invoked for the estimation, otherwise...a custom code
should go here. If the user decides to put custom code in there, he
should comment the default coding. He can then check the file's inodes,
ctimes, the phase of the moon or whatever else he deems aproppriate to
decide whether it should be backed up or not, in the given incremental
level and/or date.
The way it is now, I have to change tar itself, writing a wrapper around
it, taking into account who started it, whether it was for estimation,
backup, or restore etc. This makes the task more formiddable than it
already is (for unskilled programmers like me).
By the way: Why shouldn't I be able to use dump for the estimations and
tar for the backups (and vice-versa)? This solution (assuming it is one,
i.e. assuming that dump estimates correctly where tar does not), is less
general than the above, but should take you only another parameter in
amanda.conf and some case checking to implement with the existing code.
--
Regards
Chris Karakas
Don´t waste your cpu time - crack rc5: http://www.distributed.net
