Re: DHCP assigned unregistered IP address
Bob Hall wrote: 1) It is a Motorola cable modem. (SB5100) The modem web page contained this: The SURFboard cable modem can be used as a gateway to the Internet by a maximum of 32 users on a Local Area Network (LAN). When the Cable Modem is disconnected from the Internet, users on the LAN can be dynamically assigned IP Addresses by the Cable On the SB4100, the Enable DHCP checkbox is right above this blurb. However, note the When the Cable Modem is disconnected from the Internet... so the only reason it should be handing you the local IP is if it cannot talk back to the DHCP server it gets your real IP from. If it happens again, you might want to talk to your provider to find out *why*. Does this thing have any flashing lights on the front? --Alex ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
On Fri, Jul 15, 2005 at 11:38:07AM +0100, Alex Zbyslaw wrote: Bob Hall wrote: The modem web page contained this: The SURFboard cable modem can be used as a gateway to the Internet by a maximum of 32 users on a Local Area Network (LAN). When the Cable Modem is disconnected from the Internet, users on the LAN can be dynamically assigned IP Addresses by the Cable On the SB4100, the Enable DHCP checkbox is right above this blurb. Yes, I've seen screen shots with it. The SB5100 has no checkbox. However, note the When the Cable Modem is disconnected from the Internet... so the only reason it should be handing you the local IP is if it cannot talk back to the DHCP server it gets your real IP from. If Yea, that's pretty obvious. It's also pretty undesirable. Apparently, Motorola decided the checkbox was confusing and removed it, replacing it with this automatic behavior. Blea. it happens again, you might want to talk to your provider to find out *why*. Does this thing have any flashing lights on the front? There are LEDs, but they didn't indicate anything was wrong. There have been many reboots over the time I've been with this ISP, and this is the only time this happened. I'm not going to demand an explanation for a fluke. A better question is why the tech I talked to told me that the unregistered IP address wasn't a problem. But she did tell me that she was new, and generally the techs can distinguish between their cloacal anatomy and a geophysical excavation. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
Bob Hall wrote: However, note the When the Cable Modem is disconnected from the Internet... so the only reason it should be handing you the local IP is if it cannot talk back to the DHCP server it gets your real IP from. If Yea, that's pretty obvious. It's also pretty undesirable. Apparently, Motorola decided the checkbox was confusing and removed it, replacing it with this automatic behavior. Blea. Learning from Microsoft ;-) If it happens again, you might want to talk to your provider to find out *why*. Does this thing have any flashing lights on the front? There are LEDs, but they didn't indicate anything was wrong. There have been many reboots over the time I've been with this ISP, and this is the only time this happened. I'm not going to demand an explanation for a fluke. I just meant that it might indicate a fault somewhere in either your modem or (more likely) some of the hardware between it and the ISP. Somewhere I have a list of acceptable values for some of the (to me) impenetrable signal levels etc. which my 4100 can show me. At least if I see one of those is bad, then I know it's not my fault. If things don't return to normal in a while, then maybe it's worth contacting tech support or checking their status page (which I can only do because I still have a separate dial-up account for just such emergencies). Also if the 4100 can't reach the DHCP server, the green lights won't ever all come on, so it's pretty obvious when there is a fault. Of course, that might be because the local DHCP server has been turned off ;-) A better question is why the tech I talked to told me that the unregistered IP address wasn't a problem. But she did tell me that she was new, and generally the techs can distinguish between their cloacal anatomy and a geophysical excavation. My experience of virtually every large organisation is that there are two types of techs. The ones for whom their cloacal anatomy is indistinguishable from their articulatio cubiti, and the ones who actually know how to listen, diagnose a problem etc. With the rise in call centres, the former are becoming more prevalent, and it gets harder to get your problems referred to the latter. When the person you talk to has a script which doesn't go beyond turn if off; leave it for 30 seconds and turn it back on again, you are in trouble. --Alex ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
On 7/15/05, Alex Zbyslaw [EMAIL PROTECTED] wrote: Bob Hall wrote: However, note the When the Cable Modem is disconnected from the Internet... so the only reason it should be handing you the local IP is if it cannot talk back to the DHCP server it gets your real IP from. If Yea, that's pretty obvious. It's also pretty undesirable. Apparently, Motorola decided the checkbox was confusing and removed it, replacing it with this automatic behavior. Blea. Learning from Microsoft ;-) If it happens again, you might want to talk to your provider to find out *why*. Does this thing have any flashing lights on the front? There are LEDs, but they didn't indicate anything was wrong. There have been many reboots over the time I've been with this ISP, and this is the only time this happened. I'm not going to demand an explanation for a fluke. I just meant that it might indicate a fault somewhere in either your modem or (more likely) some of the hardware between it and the ISP. Somewhere I have a list of acceptable values for some of the (to me) impenetrable signal levels etc. which my 4100 can show me. At least if I see one of those is bad, then I know it's not my fault. If things don't return to normal in a while, then maybe it's worth contacting tech support or checking their status page (which I can only do because I still have a separate dial-up account for just such emergencies). Also if the 4100 can't reach the DHCP server, the green lights won't ever all come on, so it's pretty obvious when there is a fault. Of course, that might be because the local DHCP server has been turned off ;-) A better question is why the tech I talked to told me that the unregistered IP address wasn't a problem. But she did tell me that she was new, and generally the techs can distinguish between their cloacal anatomy and a geophysical excavation. My experience of virtually every large organisation is that there are two types of techs. The ones for whom their cloacal anatomy is indistinguishable from their articulatio cubiti, and the ones who actually know how to listen, diagnose a problem etc. With the rise in call centres, the former are becoming more prevalent, and it gets harder to get your problems referred to the latter. When the person you talk to has a script which doesn't go beyond turn if off; leave it for 30 seconds and turn it back on again, you are in trouble. You must use comcast. :) --Alex ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
On Fri, Jul 15, 2005 at 07:14:52PM +0100, Alex Zbyslaw wrote: Also if the 4100 can't reach the DHCP server, the green lights won't ever all come on, so it's pretty obvious when there is a fault. Of course, that might be because the local DHCP server has been turned off ;-) In this case, the green lights were on. It seems as though the failure to contact the DHCP server was only momentary, but just long enough to ensure that my gateway box was assigned an unregistered IP address by the modem. The order of events was roughly 1) DHCP server off line 2) Modem fails to contact server 3) Modem assigns unregistered IP address to FBSD box. 4) DHCP server comes back on line 5) I check modem lights, which are all green, since the modem can now communicate with the server. was new, and generally the techs can distinguish between their cloacal anatomy and a geophysical excavation. two types of techs. The ones for whom their cloacal anatomy is indistinguishable from their articulatio cubiti, and the ones who Damn. Trumped by medical Latin. I hate it when that happens. :) ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
Hornet wrote: On 7/15/05, Alex Zbyslaw [EMAIL PROTECTED] wrote: When the person you talk to has a script which doesn't go beyond turn if off; leave it for 30 seconds and turn it back on again, you are in trouble. You must use comcast. :) Actually, Blueyonder/Telewest. The same madness exists both sides of the Atlantic :-( --Alex ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
Bob Hall wrote: two types of techs. The ones for whom their cloacal anatomy is indistinguishable from their articulatio cubiti, and the ones who Damn. Trumped by medical Latin. I hate it when that happens. :) Well, one has to rise to a challenge :-) (And I'll admit cheating and using wordnet http://wordnet.princeton.edu/perl/webwn) --Alex ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
Bob Hall wrote: Tonight, during a thunderstorm, I shutdown the household FBSD internet gateway. After the storm passed, I booted it up again, only to discover that during the bootup, my ISP's DHCP server had assigned me a new IP address. That wasn't a problem in itself, but the new address was 192.168.100.11, an unregistered address. As suggested, the cable modem is probably the culprit. If you do not need it's DHCP, can you talk to it by http? Mine is 192.168.100.1 and has a tickbox to turn DHCP on/off on its config page. The trouble then is that you can have *no* IP address if you cable is down, but at least it's clear what's going on. --Alex ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
At 10:29 PM 7/13/2005, Robert Huff wrote: Glenn Dawson writes: Sounds like you have one of the motorola cable modems. They will assign exactly that address if they are turned on and can't communicate with the cable companies network. In such situations, my 3Com shows a red light in the appropriate slot. Do Motorolas not do this? On the one I have (SB3100) the power light will blink under some circumstances, such as the ISP turning you off for not paying your bill. You can also point your browser at http://192.168.100.1/ and get various bits of info from the unit itself. (that will work if you end up with an addr assigned by your ISP or from the motorola unit) Documentation for the various models is here: http://broadband.motorola.com/noflash/customer_docs/user.html -Glenn Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
On 7/14/05, Robert Huff [EMAIL PROTECTED] wrote: Glenn Dawson writes: Sounds like you have one of the motorola cable modems. They will assign exactly that address if they are turned on and can't communicate with the cable companies network. In such situations, my 3Com shows a red light in the appropriate slot. Do Motorolas not do this? Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] When you try to go to any web site, is it redirection you to the same web page? Also try 'dig @216.235.128.31 www.yahoo.com' and 'dig @216.235.128.31 www.freebsd.org' and if you get the same IP, you might need to re-register with your ISP. I had a similar problem, where their DHCP server got hosed and I experienced the same issue. Also :) did you pay your bill. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
Thanks for all the replies. Responses to everyone's comments and suggestions: 1) It is a Motorola cable modem. (SB5100) 2) I can access 192.168.100.1 after modifying the firewall rules that stop RFC1918 nets on the outside interface. (IPFW) There's no checkbox to disable DHCP. I downloaded the modem user manual from the URL Glenn Dawson posted, but I didn't find anything on this problem. 3) I did the (shutdown, disconnect modem 30 seconds, reboot) cycle about three times, but it didn't do anything. The solution was # dhclient -r # dhclient rl0 Repeat until oip != 192.168.100.11. (I think it took four iterations, but I wasn't counting.) This cleared the IP address on both the inner and outer NICs. Maybe I should have specified the interface with the -r flag, but it was easy to fix. 4) The problem was solved by the time I saw the dig suggestion, so I didn't have a chance to try it. 5) Bill was paid on time. :) The modem web page contained this: The SURFboard cable modem can be used as a gateway to the Internet by a maximum of 32 users on a Local Area Network (LAN). When the Cable Modem is disconnected from the Internet, users on the LAN can be dynamically assigned IP Addresses by the Cable Modem DHCP Server. I take this to mean that the modem can't do NAT. It can only act as a gateway for registered IP addresses, which it can't assign. The config web page has two buttons: Reset All Defaults Restart Cable Modem I can't find any documentation on the second. Would Restart Cable Modem be equivalent to disconnecting the modem power for 30 seconds? And Reset All Defaults would have released the unregistered IP address? (Along with any other settings) How do I find the outward facing IP address for the cable modem? Is that the option routers line in dhclient.leases? ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
Most cable modems have an RCF1918 on their external management address. This is not part of the routing you see. The modem bridges your NIC to the Cable headend interface - like a layer 2 ethernet. Do a TCPDUMP on your external interface. Here in Cox Cable land you will see packets from 10.x.x.x every once in a while. This is the traffic from you modem to the headend for management. On Jul 14, 2005, at 10:56 AM, Bob Hall wrote: Thanks for all the replies. Responses to everyone's comments and suggestions: 1) It is a Motorola cable modem. (SB5100) 2) I can access 192.168.100.1 after modifying the firewall rules that stop RFC1918 nets on the outside interface. (IPFW) There's no checkbox to disable DHCP. I downloaded the modem user manual from the URL Glenn Dawson posted, but I didn't find anything on this problem. 3) I did the (shutdown, disconnect modem 30 seconds, reboot) cycle about three times, but it didn't do anything. The solution was # dhclient -r # dhclient rl0 Repeat until oip != 192.168.100.11. (I think it took four iterations, but I wasn't counting.) This cleared the IP address on both the inner and outer NICs. Maybe I should have specified the interface with the -r flag, but it was easy to fix. 4) The problem was solved by the time I saw the dig suggestion, so I didn't have a chance to try it. 5) Bill was paid on time. :) The modem web page contained this: The SURFboard cable modem can be used as a gateway to the Internet by a maximum of 32 users on a Local Area Network (LAN). When the Cable Modem is disconnected from the Internet, users on the LAN can be dynamically assigned IP Addresses by the Cable Modem DHCP Server. I take this to mean that the modem can't do NAT. It can only act as a gateway for registered IP addresses, which it can't assign. The config web page has two buttons: Reset All Defaults Restart Cable Modem I can't find any documentation on the second. Would Restart Cable Modem be equivalent to disconnecting the modem power for 30 seconds? And Reset All Defaults would have released the unregistered IP address? (Along with any other settings) How do I find the outward facing IP address for the cable modem? Is that the option routers line in dhclient.leases? ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to freebsd-questions- [EMAIL PROTECTED] ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
At 09:49 PM 7/13/2005, Bob Hall wrote: Tonight, during a thunderstorm, I shutdown the household FBSD internet gateway. After the storm passed, I booted it up again, only to discover that during the bootup, my ISP's DHCP server had assigned me a new IP address. That wasn't a problem in itself, but the new address was 192.168.100.11, an unregistered address. The result was that I could ping my ISP's DHCP server, but I couldn't do anything that required a URL. When I talked to a tech at my ISP, she couldn't see my modem. She insisted that the IP address wasn't a problem because I had a router. (Huh?) After she scheduled a visit from a tech for tomorrow and I hung up, I released the lease on the unregistered address a few times until the DHCP server gave me a new, registered address. Magically, everthing worked again. When I cancel the tech visit tomorrow, I'll have them check to see if they can see my modem again. Obviously, the unregistered IP address screwed up my system and theirs. Sounds like you have one of the motorola cable modems. They will assign exactly that address if they are turned on and can't communicate with the cable companies network. My understanding, after extensive reading, is that the unregistered address could only have come from my ISP's DHCP server. However, I don't know why they would have assigned an IP address that screwed up their systems and mine. I'm wondering if dhclient could have assigned this address to itself if it encountered a problem during bootup. I don't believe this could happen, but I don't understand why my ISP would shoot itself (and me) in the foot. Does anyone know enough about dhclient to say definitely whether it could have been the culprit? Anybody with enough experience with ISPs to say why they would have assigned an unregistered IP address that broke both systems? see above. -Glenn ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: DHCP assigned unregistered IP address
Glenn Dawson writes: Sounds like you have one of the motorola cable modems. They will assign exactly that address if they are turned on and can't communicate with the cable companies network. In such situations, my 3Com shows a red light in the appropriate slot. Do Motorolas not do this? Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]