Mksquashfs is failing

Nerves Forum Nerves Questions / Help
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3

Thanks for much for you help.
Yes, I am using Linux (Ubuntu 18.04)
Below is info on version of mksquashfs.

~/work/pp/nerves/bb/test_bb$ mksquashfs -version
mksquashfs version 4.3-git (2014/06/09)