networking problem

[Tim]

On Thu, 2009-06-18 at 14:40 -0700, Gerhard Magnus wrote:
> I recently added a D-Link wireless router to a network in which
> everything (except a new netbook computer) is connected by ethernet
> cables. I also use static addresses. Here's the setup:
> 
> DSL modem --> Linksys router --> D-Link router --> wireless netbook
>                     |
> 		    -----------> eternetted computers	
> 
> Using a browser on the netbook I can access configuration menus for both
> routers, which seems to indicate that the wireless network was set up
> correctly and that the cable between the two routers is working.

I use the same set up, also with a D-link wireless router.  (Not too
thrilled with it, I think their web configurator is a nightmare.)

> I cannot access the configuration menu of the DSL modem from the
> netbook, although I can do this from any of the other computers.

That's common enough, it stops neighbours reconfiguring your router,
remotely, by accident (e.g. if you have an unencrypted link), or by
subterfuge (e.g. if they crack low grade encryption), since it's simply
not accessible to them.  There's a configuration option on many wireless
routers about whether the configurator can only be accessed over the
wired connection.  Generally, this is a good idea.

On some devices, they come preconfigured to use no encryption and allow
remote configuration over the wireless connection.  The first time a
user configures their wireless device, they broadcast all their
passwords in the clear, for anyone around them to hear.  I make the
first connection using a cable, then turn off the remote wireless access
until I've finished securing the device.

> Consistent with this, I cannot access the Internet from the netbook,
> either with named or with IP addresses.

Perhaps that's down to you using static addressing?  On my system, I
have a central DHCP server, and that tells all devices what the
addresses and routes are.  But the LAN side of my D-link doesn't seem to
work with DHCP, I set *it* manually, the rest of my system is automatic.

If you manually configure a device, you may have forgotten to set a
route.  If the wireless router is acting as a router, rather than as a
dumb access point, it may not relay traffic through unless you've
configured it with a gateway address.

My D-link has manually set into it:
  its own address
  its netmask
  gateway address (my modem/router's LAN address, it's my gateway to
                   the ISP)

I'm guessing that you've missed the last one.  Set your Linksys router's
LAN IP address as your D-Link router's gateway address.

-- 
[tim at localhost ~]$ uname -r
2.6.27.24-78.2.53.fc9.i686

Don't send private replies to my address, the mailbox is ignored.  I
read messages from the public lists.