Re: [gentoo-user] Disable IPv6 on specific interface

[covici@ccs.covici.com]

Zesen Qian <gentoo-user@dnspod-free.mydnspod.net> wrote:

> covici@ccs.covici.com writes:
> 
> > Mick <michaelkintzios@gmail.com> wrote:
> >
> >> On Tuesday 30 Dec 2014 03:27:34 Zesen Qian wrote:
> >> > Hello list,
> >> > Sorry for hijacking Rich's thread, resend here.
> >> > I want to disable IPv6 on an certain interface, a simple google
> >> > tell me to add one line to /etc/sysctl.d/local.conf
> >> > net.ipv6.conf.enp4s0.disable_ipv6=1
> >> > Simple enough, but the problem I have is that both ipv6 and the
> >> > dirver of the network card(tg3) is loaded by modules. They 're not
> >> > loaded when the service sysctl is started, so there's no entry
> >> > named "net.ipv6.conf.enp4s0", which make sysctl not working.
> >> > So my question is that, is there any way to disable IPv6 on
> >> > specific interface, as early as I can? I want to make it early
> >> > because I don't want to receive any RA to mess up my route table.
> >> > I guess just adding sysctl to preup() in /etc/conf.d/net should do
> >> > the trick, but may I make it earlier?
> >> > Any comment is appreciated.
> >> 
> >> 
> >> Unless the kernel knows of the enp4s0 interface and therefore lists it under 
> >> sysctl, I can't see how it can be disabled.  You could try disabling IPv6 
> >> altogether in the kernel, but this may not be what you want to achieve.
> >> 
> >> Alternatively, have a look with modinfo in the module options in the unlikely 
> >> chance that the module has some option which disables IPv6 functionality.
> >
> > You may be able to use the feature of modprobe that executes a command
> > when the module loads and that way disable the ipv6 interface.  I have
> > not tried this myself.
> 
> Hello Covici,
> Yes, there's a rule named "install <modulename> [command..]" in
> modprobe, but aren't they only applied to modprobe itself? I mean, in my
> case the ipv6 and tg3 is loaded automatically(maybe by udev?), not by
> running "modprobe ipv6". is this kind of module loading also affected by
> modprobe rule(in /etc/modprobe.d/*.conf)?

I think so, as I use it for my soundcard modules which udev loads.

-- 
Your life is like a penny.  You're going to lose it.  The question is:
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you spend it?

         John Covici
         covici@ccs.covici.com