# ProxyARP Subnetting - SIOCSARP: Invalid argument

## sneak147

Hi,

i want to put a machine (which is running ntop) between a live switch and firewall, so this machine that has to be made transparent, so ive decided to use the methods mentioned at:

http://www.linuxjournal.com/article.php?sid=3246

 and

http://www.tldp.org/HOWTO/Proxy-ARP-Subnet/setup.html

Now when I enter the following command,

```
arp -v -i eth1 -Ds 172.69.128.128 eth1 netmask 255.255.255.128 pub

```

I keep getting the following error,

 *Quote:*   

> [root@localhost root]# arp -v -i eth1 -Ds 172.69.128.64 eth1 netmask 255.255.255.192 pub
> 
> arp: device `eth1' has HW address ether `00:50:8B:8B:4D:C6'.
> 
> arp: SIOCSARP()
> ...

 

Is anyone able to help, I know this might not be gentoo related.  :Wink: 

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