Thanks, Issues, and Suggestions

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Small update... it has the same file size limit using an ext2 partition. Weird.

There are no file size limits, e.g. by running "ulimit -a".

My only guess now is that the kernel or dd weren't compiled with LFS, e.g. the _FILE_OFFSET_BITS are not correct...

19:53, 2 January 2015

I confirmed this on a rev. C board. The images are limited to 2Gb. I agree that it looks like the save-emmc image was not compiled with large file support. There's a way around it though, I added on-the-fly compression to commands in aurorun.sh:

  1. backup

dd if=/dev/mmcblk1 bs=100M | gzip -c > /mnt/BBB-eMMC-$RANDOM.img.gz >>/mnt/autorun.log 2>&1

  1. restore

gunzip -c /mnt/BBB-stockDebian.revC.img.gz | dd of=/dev/mmcblk1 bs=100M >>/mnt/autorun.log 2>&1

(thanks for the idea to send the output to a log file by they way, this adaptation gets both stdin and stdout) It takes a lot longer: >20 minutes to compress and ~15 to decompress but the resulting stock debian image is 572 megabytes. That's from a 4 gig eMMC that is 42% full. That means that unless you are trying to image an eMMC drive full of compressed movies or images then it should always fit under the 2 gig limit, plus you can fit more images on your SD card.

15:35, 5 January 2015

Thanks for the confirmation! I thought I was going crazy...

I like the fix too. I ended up just booting a full stock image and dd'ing the image that way, but this is probably better. I guess I was kind of worried it wouldn't be able to read past the 2GB limit on mmcblk1 either.

16:12, 6 January 2015

Agreed that the 2GB limit isn't on all FAT partitions, only non-FAT32 partitions. This really isn't an issue with the shared image as I don't provide the format information (which makes it easier to work with non-Linux systems). The work-around of always compressing the images seems practical, so I added it to my image.

Thanks for all your trouble-shooting!

08:34, 6 February 2015

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