[Q]how to fully backup on a screen-broken phone through command line

the nexus 6 is rooted, running 5.1.1.
the screen is totally broken, cannot see anything on it.
is there anyway to do a full backup like the one in TWRP recovery through command line to fully copy the contents out.
then I can copy the data to a new nexus 6 phone.

Thanks in advance.

[Q]How can I temporary boot a custom kernel using adb?

Hi,
I want to temporary boot my nexus 6 with ElementalX.
I'm familiar with the fastboot command fastboot boot boot.img
But what boot img I need to use after downloading the flashable zip file of the kernel?
Pics provided below, which file I need to use for the fastboot command?

Attached Thumbnails