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I have a Linksys WRT54G2 router. I have an network with the router as the default gateway at The DHCP starts at 101 and allows for 50 licenses. My hardwired computers go from to .4. When I try to forward a port to, and hit save settings, a message pops up that says "Invalid ip address". I do not get the issue, I can ping from the router.


locked by HopelessN00b Dec 5 '14 at 12:22

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I can assign to, so I assuming it is an issue with the router holding .1 for some reason, I am just trying to keep these certain devices out of the DHCP range – Kevin May 28 '09 at 16:53
up vote 2 down vote accepted

Maybe the firmware just assumes the the first IP address in the range is a router or gateway, which you wouldn't likely be forwarding ports to.

Can you set it to forward to

This would be my first check also. Look to see if there's a firmware upgrade for that router. – squillman May 28 '09 at 16:57

The first and last IP addresses in any range are reserved. In this case, is the gateway address, and should normally be the address of the gateway router.

Try putting your Linksys at and/or moving the other machine to a new address.


Assumption is that you're trying to DNAT traffic from the outside to a specific port, to on the same or some other port; Your rule needs to include the following components...

  • source (or equivalent - the Internet/Any)
  • destination (your router's Internet-facing IP address, not which seems to be your internal network)
  • destination port - whatever port you want to DNAT
  • DNAT destination -
  • DNAT port - whatever

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