Status code "-1" in logs (3 replies)

Good Morning,

I was spying on my logs and something out of the ordinary popped out at me. We are getting a status code of -1. The status CDNN is odd enough as it is… Why would this be?

Jan 18 13:47:18 example.com Jan 18 20:47:18 haproxy[23541]: 10.0.0.1:24550 [18/Jan/2017:20:47:16.412] fe~ be/10.1.0.1:3001 282/0/1490/-1/1824 -1 503 - - CDNN 2296/96/12/4/0 0/0 "GET /healthcheck HTTP/1.1"
Jan 18 13:44:01 example.com Jan 18 20:44:01 haproxy[23445]: 10.0.0.1:2650 [18/Jan/2017:20:43:59.295] fe~ be/10.1.0.1:3001 501/0/1349/-1/2079 -1 503 - - CDNN 2249/86/6/1/0 0/0 "GET /healthcheck HTTP/1.1"