On Saturday 23 September 2017 07:43:14 Jonathan Wilson wrote: > On Fri, 2017-09-22 at 22:07 -0400, Gene Heskett wrote: > > Greetings; > > > > Trying to dd a copy of the micro-sd card the pi-3b is booting from, > > to another micro-sd card in a usb reader/writer, and winding up with > > nothing but an empty lost+found directory on it. > > > > Obviously some sort of a syntax error, but it still takes the pi > > several hours to do it, with the traffic led on the reader/writer > > showing continuous activity. > > > > Is there another way/util that actually works for making verbatim > > backups of these limited lifetime sd cards? > > > > Thanks. > > > > Cheers, Gene Heskett > > I used to use dd quite a lot, usually to a file (from a disk) as I was > playling with virtual boxes quite a bit. It "may" be that the dd is > not from the disk, but is from a partition... or some other variation > on the theme (1). Also, its worth typing sync after the dd to make > sure that all disk access (write) is coalesced. If I recall correctly, > once the sync returns to the command line then there are no more > pending writes so even pulling the SD (not correctly > un-mounting/ejecting it) shouldn't corrupt it. > All followed and understood. > > (1) When dd'ing between physical drives I always made sure they were > matched size wise, which was probably not required but I had it in my > head that dd'ing a drive including the partition table to a larger > sized drive would cause issues. Where the drives were unmatched I'd > set the new partition(s) manually, and then dd the partitions one at a > time and I always made sure the too partition was set up to be the > same size as the from partition (even if the location differed) and > then do any re-sizing of the cloned partition & file system upwards > afterwards. As I say, possibly not required in some/all cases but gut > feelings are hard to overcome as I had it in my head - something to do > with backup tables set at the far end of partitions.
humm... backup inodes are generally at 8k offsets from the starters location, or so I've read. And why, when I click on reply to list, do I get blank to: lines and have to manually copy them from the incoming email? Its a right pita. 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) Genes Web page <http://geneslinuxbox.net:6309/gene>