M-s s

(defun ssh-to-host (x)
   "Ask for host."
   (interactive "sHost: ")
   (let* ((buffer-name (format "*SSH %s*" x))
	    (buffer (get-buffer buffer-name)))
     (if buffer
	   (switch-to-buffer buffer)
	 (multi-term)
	 (term-send-string
	  (get-buffer-process (rename-buffer buffer-name))
	  (format "ssh %s\r" x)))))

 (global-set-key (kbd "M-s s") 'ssh-to-host)