scan for open public ssh ports on your hosts

public_ssh_scan.sh

#!/bin/bash

ip_list=$(knife joyent server list | awk '{print $7}' | cut -d"," -f 1 | grep -v "10.*\|192.168.*\|172.16.*")

for ip in $ip_list
  do nmap -A -T4 -F $ip
done | grep "Nmap scan report\|ssh"

If you're not using knife and the knife-joyent gem/plugin for knife, then you'll probably want to customize line 3.

You should be able to run this directly from this Gist by doing https://gist.githubusercontent.com/bixu/641b0d22f3353b846726/raw/public_ssh_scan.sh | bash -s