View gist:1cec0dd60527b408b681964cc1f1daff
# First, enable SSH in the Administration->System tab.
# Then log in to the device.
# Verify that https_crt_save is off
admin@RT-N66U:/tmp/home/root# nvram get https_crt_save
0
# Enable https_crt_save and verify that it was set correctly
admin@RT-N66U:/tmp/home/root# nvram set https_crt_save=1
admin@RT-N66U:/tmp/home/root# nvram get https_crt_save