On 19 September 2016 at 20:13, Neil Greenwood <neil.greenwood....@gmail.com> wrote: > Sorry for the top post, I'm on my phone. > > I think partimage does what you want already. Clonezilla gives a (very > slightly) friendlier front end, but I've not used either for several > years...
I believe partimage does not handle ext4 which would be a problem (at least that is what [1] says) I had thought about clonezilla and will have another look at it. The last time I used it (which was some time ago) it seemed overly complex, but perhaps I just need to put a bit more effort in to see how to use it from a script. Thanks Colin [1] https://www.partimage.org/Main_Page > > > Neil > > On 19 September 2016 17:49:44 BST, Colin Law <clan...@gmail.com> wrote: >> >> On 19 September 2016 at 17:18, Robert McWilliam <r...@allmail.net> wrote: >>> >>> On Mon, 19 Sep 2016, at 14:21, Colin Law wrote: >>>> >>>> I do a fair amount of work with SD cards and use dd to create an image >>>> for backup or for burning onto other cards. If I burn an image from an >>>> 8GB card onto a 16GB card then I get a card which is only half used. >>>> If I then make an image from that one then I get a 16GB image (of >>>> which only 8GB or less is partitioned) which is larger than it needs >>>> to be and also if I burn that onto another 8GB card then it fails as >>>> the card is not large enough (or at least it says it has failed, the >>>> card will in fact be ok). >>> >>> >>> You can copy a single >>> partition by pointing dd at the partition rather >>> than the device, e.g. sda1 rather than sda. I expect that would achieve >>> the same thing as giving dd offset and size that you can get from fdisk >>> (but less likely to get those wrong). >>> >>> Neither approach will give you an image that you can (reliably) put back >>> onto a card with (just) dd. It won't include the partition table. >> >> >> Is not the partition table in the space before the first partition? So >> in the example I posted where I had >> >> Device Boot Start End Sectors Size Id Type >> /dev/sdb1 8192 137215 129024 63M c W95 FAT32 (LBA) >> /dev/sdb2 137216 4233215 4096000 2G 83 Linux >> >> is not the partition table in sectors 0 to 8191? So if I copy sectors >> 0 to 2333215 that should include the partition table and all the >> partitions. Is that not correct? >> >>> It >>> will work if the destination card is partitioned the same as the source >>> and you write to the same offset, or if you've got a partition the same >>> size and you update the offset to hit that, but otherwise you'd need to >>> update the partition table (and other partitions) to make an >>> appropriately sized gap for it and then write to that. >>> >>> I think it's better to look at what you're trying to do, and see if dd >>> is the right tool. I can understand wanting to use dd for archiving or >>> backing up cards since it'll also catch things that have been deleted or >>> lost to filesystem corruption that you can then (try to) recover once >>> you've noticed that something is missing. I'm less convinced it's a good >>> idea going the other way; it causes the problems you're seeing when >>> sizes aren't the same and it means you're writing more to the cards than >>> you need to. I >>> think you'd be better to mount the image file and copy >>> the files across to the card. >> >> >> To do it that way I believe I would have to write a script to pick up >> the partition info from the original card, mount and copy the files in >> each partition, and save the partition info with the files. Then to >> restore it I would need a script to re-partition the new card and copy >> the files across to each partition. >> >> Colin > > > -- > Sent from my Android device with K-9 Mail. Please excuse my brevity. > > -- > ubuntu-uk@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk > https://wiki.ubuntu.com/UKTeam/ > -- ubuntu-uk@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk https://wiki.ubuntu.com/UKTeam/
