I've looked at this a few times, and haven't found a solution yet.

What I want to do is open a specific port (say, 2512) for all computers connected to a linksys router. I know that I can use port forwarding to open any port or range of ports for one IP, or with the DMZ host I can open all ports, but once again this is only for one specific IP. So how can I open one port to multiple (preferably all) IPs?

2/8/2006 11:22:57 PM

look into port triggering

that doesn't fit what you're trying to do exactly.

but why would you want to open the port to all PCs? give the context - there's probably a better solution.

2/8/2006 11:25:22 PM

for two purposes really

I run a small FTP server, and the address of the computer changes from time to time on the DHCP table, so the IP address of the server isn't always the same. If I end up rebooting everything, I have to manually go into port forwarding or DMZ and make sure that the port the server is on is open for the new IP.

I also have azureus set to use a high port (~60100), and occasionaly have azureus running on more than one computer. I'd like to not have to specifically open each port for each IP when running azureus on two computers.

2/8/2006 11:38:26 PM

just configure your router to specifically assign one IP to each computer all the time rather than automatically getting the first one available.

you can do this based on MAC addresses or computer names usually in the router config.

or if it's not an option there, try manually configuring your TCP/IP options for your network card to always ask for the same IP from the router.

2/8/2006 11:41:37 PM

You can't. That's a fundamental limitation. How would the router know which computer to send it to?

The closest thing you can do is map different ports on the router to each computer's port 2512.

for example

2512 -> computer1:2512
2513 -> computer2:2512
2514 -> computer3:2512

[Edited on February 8, 2006 at 11:43 PM. Reason : ?]

2/8/2006 11:42:32 PM

try to hunt down a copy of the sveasoft firmware for the WRT54G - they charge $20/yr for it but i'm sure you can probably find it out there somewhere if you don't want to pay.

it has manual dhcp assignments by MAC address.

but in the meantime, you can try the manual IP assignments:

(tutorial: http://www.windowsnetworking.com/articles_tutorials/w2ktcpip.html )

2/9/2006 12:05:24 AM

Like someone said above...just assign IP addresses based on MAC address.

2/9/2006 8:33:37 AM

yeah that's what i do. my dlink has no problems doing that.

2/9/2006 9:16:30 AM

I was really trying to avoid specifying a static IP, but that will work seeing as how my router can't assign an IP based on MAC/computer name. I can't really install new firmware because I had to use a very specific version of linksys firmware to get it to work with a wireless repeater that I have, so i'm pretty much stuck with my current firmware.

thanks for all the help.

2/9/2006 12:46:28 PM

Why not use static IPs behind the routher?

Can you configure the port used by whatever service it is you want to forward for each computer?

Ie: HTTP

Computer 1: configure the service to use port 8080
Computer 2: configure the service to use port 8081
Computer 3: configure the service to use port 8082
ect.

Then just forward each port through for the appropriate machine.

2/9/2006 1:14:48 PM

I can vouch for the SveaSoft firmware for the WRT54G. I have used it for a while, no problems, and have been able to tell the DHCP server to assign certain IP addresses based on the requesting computer's MAC address.

On a side note, it's also good because it has built-in VPN capabilities (which I used a lot) and a whole bunch of other features that I've yet to discover.

2/9/2006 1:43:43 PM