Why is Apache2 listening on Ipv6 by default?

Question

linux

Good day.
I installed the latest version of Apache on Ubuntu, everything is standard in the config - Listen 80. However, for some reason, Apache only listens to IPv6 addresses, although it should listen to IPv4.

netstat -tlpu

Why is that? Is this a sign of problems on the server? Because when I explicitly write 0.0.0.0:80 in the config and Apache switches to IPv4, it still does not work. It is possible that the reason for these two phenomena is the same - something prevents Apache from listening to Ipv4 by default.
Thanks in advance.

Answer 1

check firewall.
and about ipv6 - this is normal behavior. In this form, he not only listens to ipv6, but also ipv4 too