check varnishadm backend health status

varnishadm.py

    #!/usr/bin/python  
    # save as /usr/lib/nagios/plugins/check_varnish_backends.py  
      
    from optparse import OptionParser  
    import subprocess  
      
    def getOptions():  
        arguments = OptionParser()  
        arguments.add_option("--host", dest="host", help="Host varnishadm is running on", type="string", default="localhost")  
        arguments.add_option("--port", dest="port", help="varnishadm port", type="string", default="6082")  
        arguments.add_option("--secret", dest="secret", help="varnishadm secret file", type="string", default="/etc/varnish/secret")  
        arguments.add_option("--command", dest="command", help="varnishadm backend health command", type="string", default="debug.health")  
        return arguments.parse_args()[0]  
      
    def run(command, exit_on_fail=True):  
        # don't use check_output in order to supportPython 2.6  
        process = subprocess.Popen(command.split(" "), stdout=subprocess.PIPE)  
        output, unused_err = process.communicate()  
        _retcode = process.poll()  
        return output  
      
    if __name__ == '__main__':  
      
        options = getOptions()  
        varnishadm_raw = run("varnishadm -T %(host)s:%(port)s -S %(secret)s %(command)s" % options.__dict__)  
      
        lines = varnishadm_raw.split("\n")  
        backends_sick, backends_healthy = [], []  
        for line in lines:  
            if line.startswith("Backend"):  
                if line.endswith("Sick"):  
                    backends_sick.append(line)  
                else:  
                    backends_healthy.append(line)  
      
        if not backends_healthy and not backends_sick:  
            print "There are NO backends"  
            exit(2)  
      
        if backends_sick:  
            print "".join(backends_sick)  
            exit(2)  
      
        print "All %s backends are healthy" % len(backends_healthy)