Is there some new kind of DHCP ? What's going on here ?

C

cbyunta88

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First, I am not necessarily asking for help or a fix ... I just want to describe what I am seeing here and see if I am crazy or not ...

I have an old d-link wifi router. Simple, does very little. Not much to say here. Has worked fine for 10 years with various ISPs who have given me *either* a dynamic IP or a fixed IP.

Now I have a new ISP, which is "exede" by viasat. It's satellite. They gave me a little modem which as far as I can tell is the same as a cable modem. Again, nothing that interesting here.

Here's the weird part...

If I plug my nice new mac laptop *directly* into the viasat modem, my mac issues a DHCP request and the modem gives it a dynamic IP (it is a REAL IP, not a private range). Everything works just fine. No problems at all.

However, of course I don't want to attach a single computer to the modem, I want to attach a wifi router, so I do.

When I plug the wifi router in, it also issues a DHCP request and ... retries over and over and over for about 2 minutes ... and finally, the modem gives it 192.168.100.3. And nothing works. That private IP does not route out to the net.

So what is going on here ?

Is there some new wrinkles to DHCP, and my new OSX mavericks knows "how to ask" properly in a way that makes the exede modem happy, and is given the "right" IP address ?

Why in the world would a device give some sorts of IP ranges to some DHCP requestors, and other types of IP ranges to other requestors ?

Exede tech support made some vague statement about there's not really a DHCP server on the exede modem, but it gives you that IP anyway, blah blah making no sense blah blah.

So I'm stumped ... my hunch is that there's some fancy new pieces to DHCP that the mac knows how to do and the DLINK router from 12 years ago does not ... this is bad behavior, of course, since the exede modem should respond properly to the old behavior, but ... maybe I'm wrong ?

Any comments or suggestions ?
 
Probably has software similar to a cable modem. Most cable modems will hand out a public ip to the first device you plug into it, then record the mac address. If you simply unplug that first device and plug in a second it with either issue a non-working private ip or nothing.

Try factory resetting the excede modem, then plugging in Your router and see what it does. if that doesn't work you need to look into the mac cloning setting on your router.
 
Another solution is check the ISP support, they may have an automated way to reset your assigned MAC on your account. Or you may have to call support and have them do it.
 
A lot of modems have a "Clone Mac Address" feature. It used to be that ISP's (like Comcast) would lock your account to the first connected Mac address, so that really used to come in handy. That was back in the day when they were anti-router and wanted you to buy additional modems for all of your computers.
 
Yeah sounds like you need to clone the MAC address on the router. I have to do the same thing with my ISP and my router.
 
Reconnect your PC to the modem. Release the DHCP lease (do not renew it), and then unconnect your PC and connect your router to the modem.
 
Skillz said:
Yeah sounds like you need to clone the MAC address on the router. I have to do the same thing with my ISP and my router.
Click to expand...
^^^This. Also, when you went to connect the wifi router to the new router, did you happen to tell the wifi router that it's no longer the Gateway?
 
Reboot the satellite modem between CPE swaps.

Just like cable modems, the modem itself learns the MAC of the device first plugged in. A reboot is needed to clear that. Cloning may not be necessary, but could also be a viable workaround.
 
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