• snmpnetstat does not show ipv6 addresses, routes, and services.

# ip a |grep inet6

# ifconfig |grep inet6

$ sudo vi /etc/sysctl.conf
....
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
....
$ sudo sysctl -p

nmcli connection modify xxx ipv6.method ignore

nmcli connection modify ens1 ipv6.method ignore
nmcli connection modify enp0s3 ipv6.method ignore

/etc/sysctl.conf or /etc/sysctl.d/disableipv6.conf

# vi /etc/sysctl.conf
...
net.ipv6.conf.all.disable_ipv6 = 1
...

# sysctl -p

echo 1 > /proc/sys/net/ipv6/conf/all/disable_ipv6
echo 1 > /proc/sys/net/ipv6/conf/default/disable_ipv6

or

sysctl -w net.ipv6.conf.all.disable_ipv6=1
sysctl -w net.ipv6.conf.default.disable_ipv6=1

/etc/modprobe.conf or /etc/modprobe.d/ipv6.conf

options ipv6 disable=1