rpmsync can be used to mirror one version of an RPM-based
distribution.  The rsync protocol allows only the differences in a
changed file to be downloaded, rather than an entire copy of a changed
file.  For RPM files, when they are updated to a new version, the
filename is changed because the version is in the filename.  rpmsync
can rename an RPM file to the new version's filename before running
rsync, to allow the efficiencies of rsync to work between different
versions of an RPM package.

rpmsync is most useful for mirroring RPM repositories that are
frequently updated.  Good exmaples are Mageia Cauldron, Mandriva
Cooker, and security updates for an RPM-based distribution.

One run of rpmsync should only be used for one version of one
distribution.  One version of a distro's security updates counts as a
different distribution.  So for example, mirroring security updates
for two different versions of Mandriva Linux would require you to run
rpmsync twice, once for each version.

rpmsync can be configured by changing the default values in the top of
the script itself, or by using command-line arguments.  Command line
arguments are the same as rsync's where appropriate, so if you are
familiar with rsync, you can use rpmsync as a drop-in replacement.
Command-line arguments used by rsync but not rpmsync will be ignored,
although warnings will be spit out to your console.  Also, for this to
work totally reliably, you need to version 2.33_02 or newer of Perl's
Getopt::Long module.

The reason rpmsync supports multiple source arguments, is because
sometimes one distribution is split into multiple directories on a
mirror, such as contrib and main for Mandriva.

Usage:
rpmsync [OPTIONS] [rsync://[RSYNCHOST]/[SRC] [LOCALPATH]]
or:
rpmsync [OPTIONS] --source=SRC [rsync://[RSYNCHOST]/[RSYNCPATH] [LOCALPATH]]

RSYNCHOST is the hostname of the rsync server you're using
The part of the path that all of your sources have in common (at the
beginning) is the RSYNCPATH.  You can determine this by browsing an
rsync server like this:
rsync rsync://[RSYNCHOST/

which will give you a directory listing.  When you pick a directory,
then run the same command, appending the path, and making sure to put
the trailing slash after the directory name.  Keep browsing until you
determine the RSYNCPATH.  Make sure to *not* have a trailing slash on
the RSYNCPATH when you call rpmsync.  The directory structure of your
sources under that path will be the same locally, and stored under
LOCALPATH.  If you have only one source, you can use the first form of
rpmsync usage, and the RSYNCPATH and SOURCES will be figured out
automatically.

An example for mirroring Mandriva Cooker i586 and x86_64 in one call:
rpmsync -vz --source=i586 --source=x86_64 rsync://ftp.uninett.no/Mandrivalinux/devel/cooker /pub/linux/Mandrivalinux/devel/cooker

An example for mirroring the security updates for Mandriva Linux 2007.0:
rpmsync -vz rsync://ftp.uninett.no/Mandrivalinux/stable/updates/2007.0 /pub/linux/Mandrivalinux/stable/updates

If you also wanted to mirror the updates for 2006.0, you would have to do
a seperate run of rpmsync.

The --include-from and --exclude-from arguments allow you to use files
with patterns to match against filenames to limit what files within
your sources you actually mirror.  By default all files within the
sources are downloaded.  You can use exclude patterns to exclude
certain files, and you can use include to make sure you don't exclude
a subset of the files that matched your exclude patterns.  rsync's
manpage has more information on the formats these files should be in.

I have included an example exclude patterns file (exclude.lst) that
will exclude packages from a Mandriva mirror that are only of use to
non-English speakers.  Thanks to Ron Stodden for this file.

If you use include/exclude patterns to exclude packages, and there is
some metadata stored within the distribution about the packages, that
metadata may need to be regenerated.  There is an example (based on
Mandriva Cooker) commented out at the bottom of the rpmsync script
that gives an idea how you can handle this.