[NTLUG:Discuss] can not ping itself.

[Richard Cobbe]

Lo, on Wednesday, May 2, MadHat did write:

> At 03:44 PM 5/2/2001 +0000, you wrote:
> 
> 
> 
> >>From: MadHat <madhat at unspecific.com>
> >>
> >>
> >>
> >>>>be.  Also, you don't have a local route to your own IP.
> >^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> >
> >then, what do you mean this?
> 
> Check the config files I mentioned.  if they are set up properly, the 
> routes should be there.
> 
> 
> >>>ok, I guess this is my problem/question.
> >>>how do I know (or check) if the ipforward is enabled?
> >>
> >>shouldn't matter for this particular issue.  ipforward is for forwarding
> >>from one interface to the other.
> >
> >I do have 2 NICs in the box. I want to make sure it is enabled.
> >I like to know how.
> 
> If it is compiled into the kernel to enable it you have to use
> # echo 1 > /proc/sys/net/ipv4/ip_forward
> to enable it...  then you have to use ipchains (depending on kernel 
> version) to set up the rules.

To check if it's enabled, you can just cat /proc/sys/net/ipv4/ip_forward.
1 says it's enabled; 0 says it's not.

And while I highly recommend the use of ipchains, you don't actually need
to use it to set up the forwarding rules; the kernel is smart enough to
figure those out on its own.

You will most likely want to use it to block certain types of traffic from
being forwarded, however.

Richard