I used JetPack 4.2 to flash my Nano manually(SDK manager), and I had put an SD card into Nano and entered recovery mode.
JetPack log
3:46:09 INFO : ========== Choose an environment ==========
13:46:09 INFO : command finished successfully
13:46:09 ERROR : Jetson device is not in recovery mode.
13:46:09 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:09 INFO : command finished successfully
13:46:09 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:09 INFO : 0) Normal
13:46:09 INFO : 1) Jetson Nano
13:46:09 INFO : 2) Jetson TX2
13:46:09 INFO : 3) NXP IMX8M
13:46:09 INFO : 4) MTK MT7686
13:46:09 INFO : command finished successfully
13:46:09 ERROR : Jetson device is not in recovery mode.
13:46:19 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:19 INFO : command finished successfully
13:46:19 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:19 INFO : command finished successfully
13:46:19 ERROR : Jetson device is not in recovery mode.
13:46:19 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:19 INFO : command finished successfully
13:46:19 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:19 INFO : 0) Normal
13:46:19 INFO : 1) Jetson Nano
13:46:19 INFO : 2) Jetson TX2
13:46:19 INFO : 3) NXP IMX8M
13:46:19 INFO : 4) MTK MT7686
13:46:19 INFO : command finished successfully
13:46:19 ERROR : Jetson device is not in recovery mode.
13:46:20 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:20 INFO : command finished successfully
13:46:20 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:20 INFO : command finished successfully
13:46:20 ERROR : Jetson device is not in recovery mode.
13:46:20 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:20 INFO : command finished successfully
13:46:20 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:20 INFO : 0) Normal
13:46:20 INFO : 1) Jetson Nano
13:46:20 INFO : 2) Jetson TX2
13:46:20 INFO : 3) NXP IMX8M
13:46:20 INFO : 4) MTK MT7686
13:46:20 INFO : command finished successfully
13:46:20 ERROR : Jetson device is not in recovery mode.
13:46:21 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:21 INFO : command finished successfully
13:46:21 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:21 INFO : command finished successfully
13:46:21 ERROR : Jetson device is not in recovery mode.
13:46:21 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:21 INFO : command finished successfully
13:46:21 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:21 INFO : command finished successfully
13:46:21 ERROR : Jetson device is not in recovery mode.
13:46:22 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:22 INFO : command finished successfully
13:46:22 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:22 INFO : command finished successfully
13:46:22 ERROR : Jetson device is not in recovery mode.
13:46:22 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:22 INFO : command finished successfully
13:46:22 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:22 INFO : 0) Normal
13:46:22 INFO : 1) Jetson Nano
13:46:22 INFO : 2) Jetson TX2
13:46:22 INFO : 3) NXP IMX8M
13:46:22 INFO : 4) MTK MT7686
13:46:22 INFO : command finished successfully
13:46:22 ERROR : Jetson device is not in recovery mode.
13:46:22 DEBUG : running command < lsusb | grep “NVidia Corp” >
13:46:22 INFO : command finished successfully
13:46:22 DEBUG : running command < lsusb | grep 0955:7020 >
13:46:22 INFO : 0) Normal
13:46:22 INFO : 1) Jetson Nano
13:46:22 INFO : 2) Jetson TX2
13:46:22 INFO : 3) NXP IMX8M
13:46:22 INFO : 4) MTK MT7686
13:46:22 INFO : command finished successfully
13:46:22 ERROR : Jetson device is not in recovery mode.
13:46:43 INFO : Device Mode Host Setup in Flash : install ‘Device Mode Host Setup in Flash’ Skipped
13:46:43 INFO : Flash Jetson Nano : install ‘Flash Jetson Nano’ Skipped
13:46:46 INFO : Device Mode Host Setup in Target SDK : install ‘Device Mode Host Setup in Target SDK’ Skipped
13:46:46 INFO : DateTime Target Setup : install ‘DateTime Target Setup’ Skipped
13:46:46 INFO : CUDA Toolkit for L4T : install ‘CUDA Toolkit for L4T’ Skipped
13:46:46 INFO : cuDNN on Target : install ‘cuDNN on Target’ Skipped
13:46:46 INFO : TensorRT on Target : install ‘TensorRT on Target’ Skipped
13:46:46 INFO : OpenCV on Target : install ‘OpenCV on Target’ Skipped
13:46:46 INFO : VisionWorks on Target : install ‘VisionWorks on Target’ Skipped
13:46:46 INFO : Multimedia API : install ‘Multimedia API’ Skipped
13:46:48 INFO : All done!
0955:7020 doesn’t match Nano’s
Bus 001 Device 046: ID 0955:7f21 NVidia Corp.
Environment
Distributor ID: Ubuntu
Description: Ubuntu 16.04.6 LTS
Release: 16.04
Codename: xenial