flash tx2 with key file hang up

I am flashing tx2 with PKC key file protected, and every time it will hang up at flashing backup.img
Writing partition APP with system.img is OK,
now what can I do to continue?

Thanks

[ 11.4736 ] […] 100%
[ 11.4756 ] Writing partition master_boot_record with mbr_1_3.bin
[ 11.5267 ] […] 100%
[ 11.5347 ] Writing partition APP with system.img
[ 11.5386 ] […] 100%
[ 77.1491 ] Writing partition mts-bootpack with mce_mts_d15_prod_cr_sigheader.bin.signed
[ 77.1661 ] […] 100%
[ 77.2861 ] Writing partition mts-bootpack_b with mce_mts_d15_prod_cr_sigheader.bin.signed
[ 77.3072 ] […] 100%
[ 77.3911 ] Writing partition cpu-bootloader with cboot_sigheader.bin.signed
[ 77.4085 ] […] 100%
[ 77.4290 ] Writing partition cpu-bootloader_b with cboot_sigheader.bin.signed
[ 77.4402 ] […] 100%
[ 77.4609 ] Writing partition bootloader-dtb with tegra186-quill-p3310-1000-c03-00-base_sigheader.dtb.signed
[ 77.4717 ] […] 100%
[ 77.5526 ] Writing partition bootloader-dtb_b with tegra186-quill-p3310-1000-c03-00-base_sigheader.dtb.signed
[ 77.5634 ] […] 100%
[ 77.5795 ] Writing partition secure-os with tos_sigheader.img.signed
[ 77.5883 ] […] 100%
[ 77.6295 ] Writing partition secure-os_b with tos_sigheader.img.signed
[ 77.6387 ] […] 100%
[ 77.6469 ] Writing partition eks with eks_sigheader.img.signed
[ 77.6524 ] […] 100%
[ 77.6642 ] Writing partition bpmp-fw with bpmp_sigheader.bin.signed
[ 77.6693 ] […] 100%
[ 77.7306 ] Writing partition bpmp-fw_b with bpmp_sigheader.bin.signed
[ 77.7427 ] […] 100%
[ 77.7718 ] Writing partition bpmp-fw-dtb with tegra186-a02-bpmp-quill-p3310-1000-c04-00-te770d-ucm2_sigheader.dtb.signed
[ 77.7857 ] […] 100%
[ 77.8366 ] Writing partition bpmp-fw-dtb_b with tegra186-a02-bpmp-quill-p3310-1000-c04-00-te770d-ucm2_sigheader.dtb.signed
[ 77.8483 ] […] 100%
[ 77.8728 ] Writing partition sce-fw with camera-rtcpu-sce_sigheader.bin.signed
[ 77.8829 ] […] 100%
[ 77.8969 ] Writing partition sce-fw_b with camera-rtcpu-sce_sigheader.bin.signed
[ 77.9040 ] […] 100%
[ 77.9158 ] Writing partition sc7 with warmboot_wbheader.bin.signed
[ 77.9235 ] […] 100%
[ 77.9612 ] Writing partition sc7_b with warmboot_wbheader.bin.signed
[ 77.9659 ] […] 100%
[ 77.9750 ] Writing partition BMP with bmp.blob
[ 77.9792 ] […] 100%
[ 78.4559 ] Writing partition BMP_b with bmp.blob
[ 78.4659 ] […] 100%
[ 78.9602 ] Writing partition kernel with boot_sigheader.img.signed
[ 78.9713 ] […] 100%
[ 79.1528 ] Writing partition kernel_b with boot_sigheader.img.signed
[ 79.1657 ] […] 100%
[ 79.1966 ] Writing partition kernel-dtb with tegra186-quill-p3310-1000-c03-00-base_sigheader.dtb.signed
[ 79.2072 ] […] 100%
[ 79.2229 ] Writing partition kernel-dtb_b with tegra186-quill-p3310-1000-c03-00-base_sigheader.dtb.signed
[ 79.2329 ] […] 100%
[ 79.2509 ] Writing partition BACKUP with backup.img
[ 79.2589 ] [ ] 000%

solved, backup img does’t accept hard/soft link.
why???

What was the actual command?

Normally the flash.sh script wants any file by the name of “system.img” in “Linux_for_Tegra/bootloader/” to use. I’m not quite sure what you are asking for hard/soft link, but from the perspective of the flash software the file is just binary data. The Jetson itself has some requirements.