[CentOS] Disabling IPv4

Barry Brimer lists at brimer.org
Tue Aug 19 04:01:00 UTC 2008

On Mon, 18 Aug 2008, Robert Moskowitz wrote:

> Barry Brimer wrote:
>> On Mon, 18 Aug 2008, Robert Moskowitz wrote:
>>> Barry Brimer wrote:
>>>> Quoting Robert Moskowitz <rgm at htt-consult.com>:
>>>>> I want to seriously work with IPv6 and not have stray IPv4 functions
>>>>> messing with me.
>>>>> So in /etc/sysconfig/network, I commented out NETWORKING=yes. I have
>>>>> NETWORKING_IPV6=yes.
>>>>> In /etc/sysconfig/network-scripts I altered ifcfg-eth0, setting
>>>>> BOOTPROTO=none. That was enough for eth0 to only have IPv6 working on
>>>>> it (have IPV6INIT=yes and IPV6_AUTOCONF=yes).
>>>>> But lo had IPv4. So I commented out all of the IPV4 lines in ifcfg-lo.
>>>>> Still have IPv4 on lo. How do I disable that?
>>>> Try adding "alias net-pf-2 off" to your /etc/modprobe.conf
>>> I did that and rebooted.
>>> Then did a ifconfig and lo is still showing an inet address of
>>> and I can ping
>>> So that tends to imply that ipv4 is still running.
>> I would agree with you.
>> Have you tried setting ONBOOT=no in /etc/sysconfig/network-scripts/ifcfg-lo 
>> ??
> No, but I do want iPv6 loopback, so I need something working for ifcfg-lo
> Will try some more tomorrow....

Maybe you can try removing IPADDR and NETMASK and adding:


The complete documentation for the ifcfg files is in :

There is a log of other documentation in this file as well .. I would just 
search for ifcfg once inside the file.

Hope this helps,


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