Hello,

After I boot my Linux machine, ifconfig -a shows that I have IPV6
address:

ifconfig -a

inet6 addr: fe80::230:47ff:fe61:e5e0/64 Scope:Link

This is what is called in IPV6 a "link local" address.

Is there a way (except configuring the system not to load the ipv6
module
at startup) to avoid this link local IPv6 address?

Regards,
Ian

Hello,

ianbrn@gmail.com a écrit :
>
> After I boot my Linux machine, ifconfig -a shows that I have IPV6
> address:
>
> ifconfig -a
>
> inet6 addr: fe80::230:47ff:fe61:e5e0/64 Scope:Link
>
> This is what is called in IPV6 a "link local" address.

Indeed.

> Is there a way (except configuring the system not to load the ipv6
> module at startup) to avoid this link local IPv6 address?

The only way I know is to lower the interface MTU to a value below 1280,
which is the minimum MTU for IPv6. On older kernels, you could restore
the interface MTU to its default value afterwards, but this has been
"fixed" in newer kernels (2.6.16.x with x>=59, 2.6.22.y with y>=15,
2.6.23.z with z>=10, and 2.6.24), so IPv6 will bind to the interface
again as soon as its MTU is changed to a value above or equal to 1280.

<ianbrn@gmail.com> wrote in message
news:f632c829-71e0-4988-bf29-1a12d26a7340@a1g2000hsb.googlegroups.com...
> Hello,
>
> After I boot my Linux machine, ifconfig -a shows that I have IPV6
> address:
>
> ifconfig -a
>
> inet6 addr: fe80::230:47ff:fe61:e5e0/64 Scope:Link
> This is what is called in IPV6 a "link local" address.
>
> Is there a way (except configuring the system not to load the ipv6
> module at startup) to avoid this link local IPv6 address?

Not really. If IPv6 is present, the link local address is supposed to be
there. I don't think one can remove it (i.e. "ifconfig inet6 del ..."), but
using i6tables, one can block all IPv6 traffic so it will not leave the
system. If you don't want it there, remove IPv6 from your kernel
configuration and recompile.