Prefer IPv4 over IPv6 on CentOS 6

To prefer IPv4 (A) addresses over IPv6 (AAAA) on CentOS 6 you need to add new file named /etc/gai.conf with following content. Last line is what controls if IPv4 or IPv6 should be tried first.

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