IP-Forwarding

[Danilo Câmara]

To have IP packet forwarding enabled after reboot,
edit /etc/sysctl.conf:

# Controls IP packet forwarding
net.ipv4.ip_forward = 1

On Fri, 2005-07-08 at 22:02 -0500, Eric Hines wrote:
> I'm running FC3 2.6.11-1.35_FC3 on a server motherboard with 2 NICs.  
> I've been advised that to have IP forwarding (e.g., between subnets off 
> those NICs (I'll add a third NIC for Internet access), I must add the 
> command
> 
>     echo 1 > /proc/sys/net/ipv4/ip_forward
> 
> to the /etc/rc.d/boot.local.  This person also advises that "I may want 
> to do the echo command last and include "0" in the init scripts, since 
> it opens up your network for a short time."  But he's a SuSE guru, not a 
> Fedora Core guru.
> 
> My questions are these:  a) is this really necessary, or does the kernel 
> already include IP forwarding built in?
>     b) As FC3 does not have a boot.local file, where would I put this 
> command, if it is, in fact, necessary? At the end of 
> /etc/rc.d/init.d/xinetd, just ahead of the exit $RETVAL?  Just after 
> exit $RETVAL?
>     c) What about that 0?  Where, specifically, should it go?
> 
> Thanks for your help.
> 
> Eric Hines
> 
> -- 
> He can compress the most words into the smallest ideas of any man
> I ever met.
>   - Abraham Lincoln

-- 
Danilo Câmara <dfcamara at ic.unicamp.br>