Interesting. Want to reconfigure your system to resolve IPv4 addresses before IPv6? This may be necessary due to firewall rules to avoid slowness from IPv6 timeouts. Here’s how.
cat >/etc/gai.conf <<EOF
label ::1/128 0
label ::/0 1
label 2002::/16 2
label ::/96 3
label ::ffff:0:0/96 4
precedence ::1/128 50
precedence ::/0 40
precedence 2002::/16 30
precedence ::/96 20
precedence ::ffff:0:0/96 100
EOF
20180608/DuckDuckGo red hat resolv ipv4 address in preference of ipv6
20180608/DuckDuckGo centos resolv ipv4 address in preference of ipv6
20180608/https://askubuntu.com/questions/32298/prefer-a-ipv4-dns-lookups-before-aaaaipv6-lookups
20180608/https://wiki.vpsget.com/index.php/Prefer_IPv4over_ipv6._How_to_set_ipv4_precedence