# File lib/AWS/EC2/instances.rb, line 211 211: def monitor_instances( options = {} ) 212: options = { :instance_id => [] }.merge(options) 213: raise ArgumentError, "No :instance_id provided" if options[:instance_id].nil? || options[:instance_id].empty? 214: params = pathlist("InstanceId", options[:instance_id]) 215: return response_generator(:action => "MonitorInstances", :params => params) 216: end