[CentOS] Centos 6 - disabling IPv6 addressing

Mon Mar 9 18:35:57 UTC 2015
Robert Moskowitz <rgm at htt-consult.com>


On 03/09/2015 02:18 PM, Chris Stone wrote:
> How about, in your /etc/sysconfig/network file adding or editing the line
> for IPV6 to be:
>
> NETWORKING_IPV6=no

One of the first things I tried.  It is still in there and doing no 
difference.

What I have is:

# cat network
NETWORKING=yes
HOSTNAME=z9m9z.htt-consult.com
NETWORKING_IPV6=no
IPV6INIT=no
IPV6_AUTOCONF=no

and:

cat network-scripts/ifcfg-eth0
DEVICE="eth0"
BOOTPROTO=none
ONBOOT="yes"
TYPE="Ethernet"
NAME="System eth0"
MACADDR=02:67:15:00:00:03
MTU=1500
DNS1=50.253.254.2
DNS2=192.168.224.2
GATEWAY="50.253.254.14"
IPADDR="50.253.254.3"
NETMASK="255.255.255.240"
HOSTNAME="z9m9z.htt-consult.com"
IPV6INIT="no"

I have used all the magic glue to say "no ipv6" and it just chugs along.

>
> and then try a 'service network restart' and see what you get.
>
>
> Chris
>
>
> On Mon, Mar 9, 2015 at 11:52 AM, Robert Moskowitz <rgm at htt-consult.com>
> wrote:
>
>> No change after running this and trying both:
>>
>> system network restart
>>
>> ifdown eth0; ifup eth0
>>
>> Still having an IPv6 addr.
>>
>> The box has been up for 140 days.  Would like to keep it running...
>>
>> This box is really Redsleeve 6, which is the port of Centos 6 to arm.  The
>> kernel I am using is the F19 kernel.  All of this MIGHT be contributing to
>> things not working as they would on a 'normal' Centos box.  I am awaiting
>> the start of the Centos7-arm work ;)
>>
>>
>> On 03/09/2015 01:15 AM, Chris Stone wrote:
>>
>>> Sorry - that should be
>>>
>>>
>>> sysctl -w net.ipv6.conf.all.accept_ra=0
>>>
>>> to disable that, not 1.
>>>
>>>
>>> Chris
>>>
>>>
>>> On Sun, Mar 8, 2015 at 11:14 PM, Chris Stone <axisml at gmail.com> wrote:
>>>
>>>   Try:
>>>> sysctl -w net.ipv6.conf.all.accept_ra=1
>>>>
>>>> to persist between boots, be sure to add this to your /etc/sysctl.conf
>>>> file.
>>>>
>>>> This should prevent the box from listening to any RA announcements.
>>>>
>>>>
>>>> Chris
>>>>
>>>> On Sun, Mar 8, 2015 at 10:55 PM, Ryan Wagoner <rswagoner at gmail.com>
>>>> wrote:
>>>>
>>>>   On Fri, Mar 6, 2015 at 11:52 AM, Robert Moskowitz <rgm at htt-consult.com>
>>>>> wrote:
>>>>>
>>>>>
>>>>>> On 03/06/2015 11:00 AM, Robert Moskowitz wrote:
>>>>>>
>>>>>>
>>>>>>> On 03/06/2015 10:55 AM, Barry Brimer wrote:
>>>>>>>
>>>>>>>
>>>>>>>>    IPV6INIT="no"
>>>>>>>>
>>>>>>>>> But I am still getting a global IPv6 (and of course local scope).
>>>>>>>>>
>>>>>>>>> What else do I need to do to disable the listening for RA
>>>>>>>>>
>>>>>>>> announcements
>>>>>> and setting an IPv6 global address?  I do not want to reboot the box.
>>>>>>>>>   There are other modules, most notably bonding that rely on the ipv6
>>>>>>>> module being loaded. What I do is place "options ipv6 disable=1" in
>>>>>>>> "/etc/modprobe.d/ipv6.conf". That does require a reboot, which I know
>>>>>>>>
>>>>>>> you
>>>>>> are looking to avoid, so you may want to try other methods to remove
>>>>>>> your
>>>>>> address in the running configuration.
>>>>>>>>   'All' I need is for the system not to have a global IPv6 address.
>>>>>>> Then
>>>>>>>
>>>>>> it
>>>>>> will not try to connect to other global IPv6 systems which will reject
>>>>>> the
>>>>>> connection, as the IPv6 rDNS cannot be set, given it is a dynamic IPv6
>>>>>>> assigned address from the ISP.
>>>>>>>
>>>>>>>   I tried:
>>>>>> # cat /etc/sysconfig/network
>>>>>> NETWORKING=yes
>>>>>> HOSTNAME=z9m9z.htt-consult.com
>>>>>> NETWORKING_IPV6=no
>>>>>> IPV6INIT=no
>>>>>>
>>>>>>
>>>>>> and 'service network restart' but still showing IPv6 addressing.
>>>>>>
>>>>>
>>>>> I would try adding the below line to /etc/sysconfig/network.
>>>>>
>>>>> IPV6_AUTOCONF=no
>>>>>
>>>>> Ryan
>>>>> _______________________________________________
>>>>> CentOS mailing list
>>>>> CentOS at centos.org
>>>>> http://lists.centos.org/mailman/listinfo/centos
>>>>>
>>>>>
>>>> --
>>>> Chris Stone
>>>> AxisInternet, Inc.
>>>> www.axint.net
>>>>
>>>>
>>>
>> _______________________________________________
>> CentOS mailing list
>> CentOS at centos.org
>> http://lists.centos.org/mailman/listinfo/centos
>>
>
>