making a monitor to work

I would like to make a monitor for a microservice webserver...

It dosent seems to be thar deficult, but it does not work for me..

eks. :

if I make an curl from the loadbalancer, I get an "OK" :

curl http://10.93.0.6:28080/ping

OK

but if I try to make an monitor, it fails ??

it is made like this (copy for bigip.conf) :

ltm monitor http /Common/swarm_ping {

  adaptive disabled

  defaults-from /Common/http

  destination *:28080

  interval 5

  ip-dscp 0

  recv OK

  recv-disable none

  send "GET /ping\r\n"

  time-until-up 0

  timeout 16

}