Tim Alberts wrote:
> First,
>
> I'd like to configure my system to forward ip, to act as a gateway for
> my network. I've always used a script during startup to do this:
>
> echo 1 > /proc/sys/net/ipv4/ip_forward
> iptables -t nat -A POSTROUTING -o ${UPLINK} -j SNAT --to ${IP_NAT}
>
For ip forwarding, edit /etc/sysctl.conf and make sure you have a line
that says
net.ipv4.ip_forward = 1
For iptables, if you already have a working iptables config, just run:
service iptables save
This will create an /etc/sysconfig/iptables for you. Then make sure that
the system loads up these rules on boot with:
chkconfig iptables on
Re: your dhcp question below...you can do what you list (the man page
[man dhcp-options] and RFC2132 say they should be listed in order of
preference) but the question really is, "What will the DHCP client do
with multiple IPs in this option?" because I could see this behavior
being inconsistent.
-Shawn
> This works fine, however I want this permanent so I don't have to run
> the script on startup. I have the firewall setup with SNAT fine, but
> when I write the file /etc/sysconfig/network with the line
> 'FORWARD_IPV4=YES' it still doesn't enable the ip forwarding after boot?
>
> cat /proc/sys/net/ipv4/ip_forward
> 0
>
> So how do I do this?
>
>
> Second,
> In DHCP, you can specify multiple DNS servers:
>
> option domain-name-servers 10.0.0.1, 10.0.0.2, 10.0.0.3;
>
> can you also do this with routers?
>
> option routers 10.0.0.1 10.0.0.2;
>
> so that if one is down, the network PC's can fail over to another?
>
>
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