Hello Jon,

        first of all, thanks for your reply.

> What is this, trolling for arguments against amanda usage?

This is definitively no troll against Amanda usage. I am using it for
quite a long time without any problems (although I am missing some
usefull features, to be honest). So SORRY for any misunderstanding or
wrong words...

> How/why are you running 5 amdumps (runs per cycle)
> with only a 3 day dump cycle?

Of course I am not moron enough to run the configuration I described in
the example in real life. All I wanted was to know from an expert what
WOULD happen, if that kind of  'missing tape' problem occurs; could that
leed to data loss or not, that's all. Therefore I constructed an
example, where I could IMAGINE that something would go wrong...

> Why with such a tight setup do you have runtapes set to
> greater than 1.  With only 1 tape allowed per day you would
> have gotten a failure to backup that DLE that did not fit.
> This would have been noticed by amanda during the estimate
> phase, before the dump started and noted in the report.

That is not true, maybe. Since the data of that one client could be on
several hard disks, it would be possible to backup the client to several
tapes, as long as all the single HDs are smaller than the tape capacity.

> Even without the staged situation, amanda would have told
> you after one dumpcycle that you were about to overwrite
> your only full backup of <insert a DLE name> notifying
> you of the need for more tapes.

So, thank you, THAT is exactly the info I was looking for, because I
have not run into that situation on my site. I think, I do have enough
tapes in my cycle, even to come up with about 12 TB on 40 clients... :-)

But, if you don't mind, I would like to use the opportunity having an
expert 'on the line' and go even a little further and push that question
a little more to the extreme, just out of curiosity:

Let's assume, the five tapes from my last example were labeled
'Backup01'-'Backup05'. Now, as in the last example, this
'short-of-tapes'-problem occurs after using 'Backup02'. To avoid
overwriting 'Backup03' Amanda would kindly ask me to add another tape
(if I understood correctly). When I add the new tape, what label would
it get? 'Backup02a'? 'BackupPre03' ? '02Backup03' ?

Again, this is just to understand better, how Amanda works. I am neither
running, nor planning to run this configuration, but sometimes it's good
to try to tackle your own system down to be prepared if somebody else
tries...


With my best regards,
        Ralf





-- 

Ralf Auer       
Physics Institute IV                    Office: 2.137
University of Erlangen-Nuremberg        Phone:  +49-9131-8527087
Erwin-Rommel-Str. 1                     Fax:    +49-9131-15249
D-91058 Erlangen, Germany               Ralf.Auer AT physik.uni-erlangen DOT de