Running a server machine with CentOS 7, I've noticed that the avahi service is running by default.
I am kind of wondering what the purpose of it is.
One thing it seems to do (in my environment) is randomly disabling IPv6 connectivity, which looks like this in the logs:
Oct 20 12:23:29 example.org
avahi-daemon[779]: Withdrawing address record for fd00::1:2:3:4 on eno1
Oct 20 12:23:30 example.org
Withdrawing address record for 2001:1:2:3:4:5:6:7
Oct 20 12:23:30 example.org
Registering new address record for fe80::1:2:3:4 on eno1.*.
(the suffixes 1:2:3...
are made up)
And indeed, after that the public 2001:1:2:3:4:5:6:7
IPv6 address is not accessible anymore.
Because of that I've disabled the avahi service via:
# systemctl disable avahi-daemon.socket avahi-daemon.service
# systemctl mask avahi-daemon.socket avahi-daemon.service
# systemctl stop avahi-daemon.socket avahi-daemon.service
So far I haven't noticed any limitations.
Thus, my question about the use-case(s) of avahi on a server system.