Never take a ota update while rooted
Same thing happened to me but i learned the hard way that you should never take a OTA update while rooted because it screws things up and the phone is not stable enough to run Android OS without crashing and rebooting again. So what i did is i used RSD lite to reset to stock and after making sure root was gone i took the OTA update and now my DROID ultra is working fine
. and FYI if you still want root when running KitKat use slapmymoto to keep root it requires you to have 4.2.2 already installed and then follow some steps so you can keep root in KitKat hope it helps!