Jon LaBadie <jon AT jgcomp DOT com> writes:

>> One thing I've never understood is: WHY does Amanda need to know the
>> dumpcycle in days? If this feature has precedence over the tapecycle, it
>> is broken.
>
> I love it when someone, new to a package, can't get it to work even when
> hundreds of others are using it, says "it is broken".

Hum, I used Amanda since 1999 or so and never needed to look very
closely at any other issues than this one. I missed that there was a
runspercycle option, it had not been in my configuration I've been using
for a long time, and I do not remove commentary. (sysconftool might be
interesting for the next major Amanda version, it fills in new
parameters into an existing configuration, leaving older options
untouched.)

There is an "if" attached. Let me reword:

Amanda should NOT ONLY look at the dumpcycle, but also at the tape list,
to find when level 0 dumps are due, because a time-based scheme cannot
adjust to "one more in-between backup".

Let's see what we have:

1. tapecycle. If you re-insert a tape earlier than tapecycle allows, the
   tape will not be touched. -> There is functionality in place that
   allows to protect a tape.

2. dumpcycle. Used to force level 0 dumps AFTER N DAYS.

3. runspercycle. The exact technical function is unclear, I presume it's
   needed to map dumpcycle to a tape count.

4. Amanda defaults runspercycle to dumpcycle, assuming daily backups are
   made, rather than looking at the tapeinfo. Why that?

Let me see if I get this right: Amanda does not have an equivalent to
tapecycle that protects existing level 0 dumps. Running additional
in-between backups with too low a tape count (which can be >= tapecycle)
endangers level 0 dumps, does it? Or is some internal
runs-before-next-level-0 decreased by a manual in-between backup?

Would amanda run a new level 0 dump for a particular file system
immediately after a corresponding amrmtape? I have not seen Amanda do
that yet.

-- 
Matthias Andree

Encrypt your mail: my GnuPG key ID is 0x052E7D95