FreeBSD's refusal to connect to the internet

[Andrew L. Gould]

On Thursday 11 September 2003 08:32 am, Colin Ryan wrote:
> I have a small network of three computers in my office here.  Two Windows
> 2000, and one FreeBSD 5.1.  It's the BSD box that's giving me problems.
>
> My computers are connected to my modem via an ethernet switch. My modem is
> set up as a DHCP server, and my computers are DHCP enabled.
> When the input cable is disconnected from the modem (not the power, so it's
> still assigning IP addresses to my LAN) my BSD box picks up a valid
> internal IP address and subnet mask, it can ping and be pinged from all
> other computers on the LAN.
>
> However, when the input cable is connected to my modem, so it's connected
> to the internet, my BSD box receives nothing.  When I do an ifconfig, it
> shows NO IP address and NO subnet mask.
>
> I tried "dhclient rl0" which didn't work, so I checked /var/log/messages
> and was told "dhcp cannot bind to address; address already in use."  I then
> tried manually assigning an IP and subnet mask, which didn't work either.
>
> Getting FreeBSD online has been nothing but an ordeal, and I am about ready
> to throw in the towel.  If anyone has any ideas, I would be very grateful
> indeed.
>
> Many thanks
>
> Colin

I'm not sure it's a problem on the BSD box.

Check the cable modem and switch documentation; and review your hardware 
setup.  Make sure everything is connected properly.  For example:

I have a Linksys cable modem/router with a 4-port switch and dhcp server 
abilities.  I can attach a switch to this unit to expand its capabilities; 
but to make it work:
     1. the additional switch must be connected to a specific port; and
     2. the first port on the Linksys unit must be left unused.

Also, what IP range are you assigning via DHCP?

I hope this helps,

Andrew Gould