Originally Posted by nexuz2013
if i want to keep root after upgrade os,i have to flash factory images and root again?no better suggestion?
if i install ota updates on my rooted device What will happen?
I'll assume you have a custom recovery. The OTA may or may not flash with it, but either way, you will need to reflash SuperSU.
If the OTA fails, download the stock image from Google, extract system.img out of the archive and flash it with fastboot flash system system.img.