DNS Shutdown IPv6

DNS server found on log

APR 18:39:54 Landnsbak named[30011]: Formerr resolving ' ns-cnc2.qq.com/aaaa/in ': 125.39.57.100#53
APR 18:39:54 Landnsbak named[30011]: Formerr resolving ' ns-cnc2.qq.com/aaaa/in ': 111.161.107.195#53
APR 18:39:54 Landnsbak named[30011]: Formerr resolving ' ns-cnc1.qq.com/aaaa/in ': 111.161.107.195#53
APR 18:39:54 Landnsbak named[30011]: Formerr resolving ' ns-cnc1.qq.com/aaaa/in ': 125.39.57.100#53
APR 18:39:54 Landnsbak named[30011]: Formerr resolving ' ns-cnc1.qq.com/aaaa/in ': 111.161.104.17#53
APR 18:39:54 Landnsbak named[30011]: Formerr resolving ' ns-cnc2.qq.com/aaaa/in ': 140.207.128.140#53
APR 18:39:54 Landnsbak named[30011]: Formerr resolving ' ns-cnc2.qq.com/aaaa/in ': 111.161.104.17#53
APR 18:39:54 Landnsbak named[30011]: Formerr resolving ' ns-cnc1.qq.com/aaaa/in ': 140.207.128.140#53

Solving method

The first kind: directly compiles the configuration file/etc/sysconfig/named, removes IPv6 the parsing, only resolves IPv4

options= "Whatever" changed to Options= "-4",

Note the value of the options option can be: one of the whatever,-4,-6

Second: Disabling IPV6 is also possible.
(1) Edit the configuration file/etc/sysconfig/network, and then change Networking_ipv6=yes to Networking=no
(2) Close Ip6tables this service
(3) to the/etc/modprobe.conf file, add
Alias IPv6 off
Alias net-pf-10 off