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-   -   Persistent iptables? Where to save the script? (

GbyteSupport 12-13-2004 12:27 PM

Persistent iptables? Where to save the script?

First a bit of background: I've had a dedicated server for about 3 years and am used to basic remote adminisitration. The GUI and other features are actually a bit overwhelming...I find myself in terminal pretty often.

At any rate, I'm trying to setup a basic forwarding for my home network. It's run of the mill and it works but is not persistent after reboot or restart. Here is the script I'm using (courtesy of

# Delete and flush. Default table is "filter". Others like "nat" must be explicitly stated.
  iptables --flush           
  iptables --table nat --flush
  iptables --delete-chain   
  iptables --table nat --delete-chain

  # Set up IP FORWARDing and Masquerading
  iptables --table nat --append POSTROUTING --out-interface eth0 -j MASQUERADE
  iptables --append FORWARD --in-interface eth1 -j ACCEPT

  echo 1 > /proc/sys/net/ipv4/ip_forward

Right now I have it saved as an executable and if I reboot I come back and execute. The question I have is how do I execute this script at boot? Can I include it in a rc.d/file?

Now, I want to apologize to all the vets for such a simple question. I have UFSB and read 14 pages of threads as they releate to "gateway". Most are asking how to troubleshoot their networks and iptables for access. I did not find one explaining how to make a currenty working homenetwork persistent after reboot.

I am using CentOS v3.3 with 2 NIC's. eth0 -> internet, eth1 -> internal

All settings are good on boot (homenetwork functional, external access is good) but the forwarding has to be setup with the script above.



eantoranz 12-13-2004 12:41 PM

Well.... I have that kind of stuff (things that have to happen at boot time) at the rc.local file. I think that's the quasi-standard place to do that (in a RH-based distribution).

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