Hello!
I see a strange behaviour of the DNS resolution on version 2.0.9 and
2.0.10, but I do not know since when this happens.
On Ubuntu 18.04, I set up haproxy to use the local DNS service provided
by systemd.
Actually I see that haproxy tries to resolve the names every second.
The resolution is successful, the TTL in the answer is 1800s or longer.
The relevant configuration is the same for all "server" lines. Here an
example
[...]
resolvers systemd
nameserver local 127.0.0.53:53
[...]
backend lnxmc1-aem
mode http
timeout connect 10s
timeout server 1m
source 10.64.38.2
server xxlnxmc1-8443 xxlnxmc1.xxx.yyy.zz:8443 ssl resolvers systemd
resolve-prefer ipv4 init-addr libc,none
[...]
If I "tcpdump" the traffic, I see something like this every second for
every server name in the haproxy configuration.
07:30:58.353752 IP 127.0.0.1.46017 > 127.0.0.53.53: 30611+ [1au] A?
xxlnxmc1.xxx.yyy.zz. (46)
07:30:58.354184 IP 127.0.0.53.53 > 127.0.0.1.46017: 30611 1/0/1 A
10.64.70.4 (62)
The requester actually seems to be haproxy
$ sudo ss -np | grep 46017
udp ESTAB 0 0
127.0.0.1:46017 127.0.0.53:53
users:(("haproxy",pid=12419,fd=87))
Any ideas?
Any further configuration parameter to look at?
Thank you
.marcoc