I am running haproxy in a couple of places. It is listening on multiple
seemingly random high UDP ports.
The one running "2.6.2-ce3023-30 2022/08/03" has the following ports.
This server is in AWS. The first three lines are expected:
elyograg@bilbo:/var/log$ sudo lsof -Pn -i | grep haproxy
haproxy 1928967 root 6u IPv4 2585012 0t0 UDP *:443
haproxy 1928967 root 7u IPv4 2585013 0t0 TCP *:80
(LISTEN)
haproxy 1928967 root 8u IPv4 2585014 0t0 TCP *:443
(LISTEN)
haproxy 1928967 root 16u IPv4 2587974 0t0 UDP *:57183
haproxy 1928967 root 17u IPv4 2585855 0t0 UDP *:60746
The one running "2.7-dev2-f9d4a7-78 2022/08/05" is in my basement and
has the following ports. The first four lines are expected. There are
a lot more UDP ports active on this one.
elyograg@smeagol:~/git/lucene-solr$ sudo lsof -Pn -i | grep haproxy
haproxy 1469717 root 6u IPv4 14230127 0t0 UDP
192.168.217.170:443
haproxy 1469717 root 7u IPv4 14230128 0t0 TCP *:8983
(LISTEN)
haproxy 1469717 root 8u IPv4 14230129 0t0 TCP *:80
(LISTEN)
haproxy 1469717 root 9u IPv4 14230130 0t0 TCP *:443
(LISTEN)
haproxy 1469717 root 46u IPv4 14242826 0t0 UDP *:45727
haproxy 1469717 root 47u IPv4 14212730 0t0 UDP *:40101
haproxy 1469717 root 49u IPv4 14209917 0t0 UDP *:34584
haproxy 1469717 root 50u IPv4 14212920 0t0 UDP *:55409
haproxy 1469717 root 51u IPv4 14209875 0t0 UDP *:46192
haproxy 1469717 root 52u IPv4 14229139 0t0 UDP *:36370
haproxy 1469717 root 53u IPv4 14209916 0t0 UDP *:50898
haproxy 1469717 root 55u IPv4 14242839 0t0 UDP *:45456
haproxy 1469717 root 56u IPv4 14242890 0t0 UDP *:37717
haproxy 1469717 root 57u IPv4 14240387 0t0 UDP *:45547
haproxy 1469717 root 58u IPv4 14240302 0t0 UDP *:33960
haproxy 1469717 root 60u IPv4 14240885 0t0 UDP *:42145
These extra ports are not exposed to the world. The external firewalls
are locked down pretty well. And the hosts also have firewalls (ufw)
that are similarly restricted.
What are these ports for? They are not in the haproxy config files. I
did try searching for an explanation, and didn't find anything.
Thanks,
Shawn
