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 1000th 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/Linux
It has 2 interfaces; eth0 is configured in IPV4 for 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 and saw a nice IPV6 instead of the old IPV4 bound to ETH1.
So, action !
$ sudo vim /etc/network/interfaces allow-hotplug eth1 # was dhcp before iface eth1 inet static address 192.168.0.15 netmask 255.255.255.0 $ sudo ifdown eth1 && sudo ifup eth1
ifconfig outputs 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 is it political to influence people to adopt IPV6 ?