On Thu, Aug 25, 2005 at 05:17:50PM +0200, rangzen wrote:
> Hello,
> 
> i use amanda with a single DAT, now, i have a new automatic charger of
> 8 DAT, i want test it and run both system during one month to be sure
> of not loosing something.
> Is it possible ?
> How can i configure this ?
> 
> I found "Can I backup separate disks of the same host in different
> configurations?" at
> http://amanda.sourceforge.net/fom-serve/cache/31.html but i want
> backup the SAME disks with different configurations.
> 
> I'm affraid than amanda mix some internal file about what it backuped
> before or not ...

It is a very valid concern.  I've been thinking about it and can't give
a solid answer, but maybe some pointers.

Any answer depends in part on whether you use gnutar or some version of
dump to do your backups.  Dump traditionally has used a file in /etc
called "dumpdates" to track when it did various levels of backups.
Amanda has followed the same concept for gnutar backups by using a
file in /etc called "amandates".

If you are using a dump program amanda may not be able to control what
goes into /etc/dumpdates.  Thus there is potential for conflict between
two configs backing up the same filesystem.  Solaris' ufsdump does have
an option to specify what the entry in /etc/dumpdates should be called
but I don't know if that is common to 'all' dumps or if amanda uses it.
Your only solution in that case is to use the "record no" setting for
one config telling amanda not to update the /etc/dumpdate records.  That
will limit you to level 0's I believe for that config I believe.

If instead you are using gnutar, and thus /etc/amandates, then there is
a way to avoid conflicts.  This technique should also work if the ufsdump
option I mention above is common amongst dump programs AND amanda uses it.

A tiny section of my /etc/amandates file:

        / 0 1104304406
        / 1 1104821711
        /w 0 1104908114
        /w 1 1104821681
        /w/Packages 0 1066888427
        /w/Packages 1 1065851620
        StaticFS-1 0 1104821741
        StaticFS-1 1 1058421785
        StaticFS-2 0 1104908231
        alpha-dumps 0 1101885483
        alpha-home 0 1101885469

Note most entries are directory paths, but the last several are not.
That is the key.  In your disklist file you can name your entries
distinct from the path.  The definition of a disklist entry is:

    host name [device] dumptype [spindle [interface]]

If all your disklist entry contains is a path, it is considered both
the device (path) and the entry name.  So in your new config use a
meaningful name for each of your disklist entries.  Then as far as
I can recall all info will be recorded for the entry name, not for
the directory path.

HTH

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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