Update Parabola packages Offline

On online machine:
su -
tar cvzf varlibpacmansync.tgz /var/lib/pacman/sync/*
tar cvzf varcachepacmanpkg.tgz /var/cache/pacman/pkg/*
exit

And on offline machine:
su -
tar xvzf varlibpacmansync.tgz
tar xvzf varcachepacmanpkg.tgz
exit

You now have on the offline machine all the packages you had downloaded on the online mache.