[NCSA-discuss] wrt54gs and openwrt, rfc1918/dhcp question

[Rick DeNatale]

On 1/19/06, Steven Champeon <schampeo at hesketh.com> wrote:
>
> Hello, group.
>
> I've got a question for anyone who's used the openwrt package to replace
> the built-in functionality of a Linksys WRT54G*. Or, for anyone using
> the WRT54GS inside a larger network (as opposed to as a home cable/dsl
> access point).
>
> At the moment, our internal network is relatively simple: Linux firewall
> masquerading traffic using iptables from our rfc1918 (192.168.1.0/24)
> internal net to the outside. Works great.
>
> I've got two Apple Airport base stations (one graphite, one snow) doing
> DHCP and handing out 192.168.1.x addresses, and shuffling traffic from
> the wifi world to the hardwire world. Again, no problems, works great.
>
> Problem is, I've been asked to provide 802.11g support, and the existing
> Apples only do 802.11b. Rather than pay $250 or so for a new BS Extreme,
> I sent the CFO out to best buy and she got a WRT54GS and PC cards to
> match (oh, well - close enough; I asked her to get WRT54Gs :).
>
> Seems, however, that the s/w that comes with the WRT54GS expects to hand
> out 192.168.1.x addresses - and there's no way to change it. Also, it
> doesn't seem to want me to treat its IP as anything but 192.168.1.1.
> Well, I've already got one of those, thanks. And I'd like to be able to
> say "hey, WRT, be 192.,168.1.129, and hand out IPs from 130 to 140" or
> some such, and have it route traffic over to 192.168.1.1, my Linux
> firewall, and on the internal network.

Well my WRT54G with stock Linksys firmware lets me change it's LOCAL
IP address.  I'm running it as 192.168.0.12.  I'm not using the WAN
port at all, since it's inside my LAN, and I'm using it as an access
point rather than a router.

Right below that is the DHCP server settings.  I've got DHCP turned
off since I use another server on the lan for DHCP, but if I enabled
DHCP, it's offering 192.168.0.x as the starting client address and has
a count for maximum client count. It's keeping the client addresses
inside the subnet mask, which seems to make sense. <G>
>
> So, I've been looking at maybe throwing openwrt on it, in hopes that it
> will allow it to behave like the Apple Airports do, and let me assign an
> IP of my choosing and tell it to hand out DHCP addresses in 192.168.1.y-z
> as well, without overlapping the ranges I've already assigned to the
> DHCP server on the Airports.
>
> Anyone play with this, have any advice, warnings, recipes, etc.?
>
> It's not really that complex a network setup. But it seems to be too much
> to ask for from the WRT54GS, which is obviously targeted at your typical
> home audience.
>
> So, do I take a chance at turning it into a brick, take it back and
> trade it for a different Linksys model, or is there a trick to making
> it act like something other than a dumbed-down consumer grade AP?

It might not be an option if you recently bought it. What's the
firmware version?  If its >= Version 5 you've got one of the new
slimmed down boxes which are running VxWorks instead of Linux and
don't have enough RAM to support OpenWrt.  There's a special "classic"
WRT54GL" which was put into the product line after they switched, but
I don't believe that brick and mortar retailers are stocking it.

http://www.linuxdevices.com/news/NS4729641740.html


--
Rick DeNatale

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