On Wednesday 25 March 2020 08:51:17 gru...@mailfence.com wrote: > On Wed, 25 Mar 2020, Gene Heskett wrote: > > On Wednesday 25 March 2020 04:18:20 Andrei POPESCU wrote: > >> On Ma, 24 mar 20, 19:12:46, Gene Heskett wrote: > >>> And nothing so far, and I have been watching, in the way of > >>> reducing a filesystem to only the actual size occupied. Then it > >>> can be backed up with dd and recovered, rewritten by dd, at a > >>> reasonable size for storage. And re-expanded to fit the media it > >>> finds. > >> > >> You could do this with the 'sparse' option of dd (you might need to > >> fill the partition with a file containing only zeroes first). > >> > >> The resulting file must be handled with care as many tools (cp, > >> rsync) will un-sparse it by default, as will writing it to a > >> filesystem without support for sparse files (tar it first). > >> > >> To see the actual size with ls you will have to use -s/--size. > >> > >>> All of my attempts to do that with dd alone have been thwarted by > >>> the fact that I have yet to find two u-sd's marked as such and > >>> such a capacity, that actually were the same size. > >> > >> Just create the partitions slightly smaller than the size of the SD > >> card. > > > > I've also considered that, but then you risk losing the gpt tables > > and it all disappears in the cloud of blue smoke being emmited from > > ones ears. > > > > BTDT at least twice on arm systems. The distro folks have it and use > > it to make an install image of 5 gigs, unpacks to 7 or 8G and which > > can then be auto expanded on the first reboot to fill the card, so > > they know how to do it, why can't the user make backups from a > > deployed well running system that could be put on a fresh u-sd card > > and treated exactly the same for recovery purposes? > > could you not just dd to a file and then manipulate that file to suit > you but i would never dd a running system
Amanda has very occassional problems with that as all its backups are from a live system. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene>