block_until_instance_is_sshable.rb

require 'timeout'

def block_until_instance_is_sshable!(timeout=120)  
  start = Time.now
  while ((Time.now - start) < timeout) do
    begin
      Timeout::timeout(5) {
        # INSERT CODE HERE TO TRY TO SSH
        return true
      }
    rescue Timeout::Error
      next
    end
  end
  
  false
  
end

result = block_until_instance_is_sshable!(10)
puts result