Every time I am configuring a Debian or Centos machine with a static IP address, I forget about that behavior of not taking in account my IPV4 configuration. Then, I search for the 1000nd time the parameter to put in sysctl.conf to disable IPV6, and finally I reboot the beast.An example to illustrate :Linux deb-router 3.2.0-4-amd64 #1 SMP Debian 3.2.81-2 x86_64 GNU/LinuxIt has 2 interfaces, eth0 is configured in IPV4 since some time (1 year maybe).ETH1 is bridged on my physical network and was addressed by the DHCP, in IPV4. I talk to the VM through this interface.Tonight, I lost my Internet gateway, this device is also my DHCP server.I realized I cannot reach my VM anymore, so I checked ifconfig result and saw a nice IPV6 instead of the old IPV4 bound to ETH1.So, action ! $ sudo vim /etc/network/interfacesallow-hotplug eth1# was dhcp beforeiface eth1 inet static    address 192.168.0.15    netmask 255.255.255.0$ sudo ifdown eth1 && ifup eth1Deception :(ifconfig output only an ipv6, I cannot reach my VM. I must disable IPV6 (net.ipv6.conf.eth1.disable_ipv6 = 1) and reboot to get the connection back.I don't understand this choice to favor IPV6 over IPV4, most of people are working with IPV4 from what I know.Is it technical, or political to influence people to adopt IPV6 ?
Debian and Centos, why ipv6 prevail over ipv4
debian;centos;ipv6;ipv4