I noticed an increase of ICMP destination unreachable on thumbor cluster
https://grafana.wikimedia.org/d/000000366/network-performances-global?panelId=20&fullscreen&orgId=1&from=1559893910035&to=1559897539217
Investigating it, they're all:
127.0.0.1 > 127.0.0.1: ICMP 127.0.0.1 udp port 514 unreachable
For this kind of traffic:
127.0.0.1.46156 > 127.0.0.1.514 Msg: Jun 7 09:19:12 haproxy[2214]: [...]
From @fgiunchedi :
haproxy should be using the local syslog unix socket not udp syslog