$ wget -c http://download.wdc.com/nas/apnc-024105-034-20130215.deb $ ar xv apnc-024105-034-20130215.deb x - debian-binary x - control.tar.gz x - data.tar.lzma $ lzma -d data.tar.lzma $ tar xf data.tar $ md5sum CacheVolume/upgrade/rootfs.img d45e582743709feb305d7cabe7ecbc80 CacheVolume/upgrade/rootfs.img $ cat CacheVolume/upgrade/rootfs.md5 d45e582743709feb305d7cabe7ecbc80 -