Désactiver IPv6

Boot Linux Kernel parameter

ipv6.disable=1
# disable_ipv6=

cat > /etc/sysctl.d/70-disable-ipv6.conf <<EOF
net.ipv6.conf.all.disable_ipv6 = 1
EOF
 
sysctl -p /etc/sysctl.d/10-noipv6.conf

Si module

cat >/etc/modprobe.d/blacklist-ipv6.conf <<EOF
blacklist ipv6
install ipv6 /bin/false
EOF

/etc/apt/apt.conf.d/99force-ipv4

Acquire::ForceIPv4 "true";

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

/etc/sysconfig/network-scripts/ifcfg-eth0

IPV6INIT=no
IPV6_DISABLED=yes

nmcli connection show
nmcli connection modify Example ipv6.method disabled

/etc/default/grub

GRUB_CMDLINE_LINUX="ipv6.disable=1 crashkernel=auto rhgb quiet"

grub2-mkconfig -o /boot/grub2/grub.cfg
grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg

/etc/ssh/sshd_config

AddressFamily inet

Djava.net.preferIPv4Stack=true

/etc/systemd/system/rpcbind.socket.d/noipv6.conf

[Socket]
ListenStream=
ListenDatagram=
ListenStream=0.0.0.0:111
ListenDatagram=0.0.0.0:111

/etc/wgetrc

# To try ipv6 addresses first:
#prefer-family = IPv6

Exemple

SystemD Socket

BindIPv6Only=both

Erreur Address family not supported by protocol lors de systemctl status quand IPV6 est désactivé dans sysctl.conf.

A tester : systemctl --failed

Résolution Après avoir modifié /etc/sysctl.conf ou des fichiers dans /etc/sysctl.d/ il est nécessaire de reconstruire l'initramfs.

dracut -f -v

ifconfig | grep inet6
 
cat /proc/sys/net/ipv6/conf/eth0/disable_ipv6