Bageshwar Dham Sarkar
How did Hanuman ji tell Vibhishan to surrender to Ram?
Tie your rope to the guru's peg
Surrender is dedicating yourself at someone's feet forever. Hanuman ji told Vibhishan the one way was to tie your rope to the peg of the sadguru's feet.
Dedicating yourself at someone's feet forever is surrender. This is what is called sharanagati.