Dhcpcd rebooting router upon startup

swampdog2002 · 01-07-2008, 08:51 AM

I recently obtained a dsl connection for my home, and am using Dropline Gnome 2.20 with Slackware 12. I have enabled NetworkManager for this system. Now, each time I start up my machine, when it gets to where it attempts to obtain an IP address with dhcpcd, this process appears to hang for a long period of time, and then appears to reboot my router in the process. After it finally gets past this point, the message displayed is that it has obtained an IP address from the router, but when I then log into the router, the IP address for the machine is different. For example, the message reported from dhcpcd reports that my IP address is 192.168.1.47, but when I check this in the router it is 192.168.1.46. I am relatively new to setting up a high-speed connection, coming from years of dial-up. Any help is much appreciated. Thank you.

In addition, the router is set up as a DHCP server. The model is a Westell 327W which is from Verizon. I also experienced this problem with my OpenSuSE 10.2 machine as well.

evilDagmar · 01-09-2008, 02:16 AM

If a DHCP query is rebooting your router, it's a safe bet that it's time to replace the router. ISC's dhclient doesn't do anything fancy when it makes it's query, and that's what dhcdbd is calling to get an IP.

swampdog2002 · 01-09-2008, 07:47 AM

The router is brand new, and I don't have this problem otherwise. It's strange that I have NetworkManager now enabled on an openSuSE 10.3 computer and this does not appear to happen. It doesn't really matter to me, as I can utilize the network w/o the use of NetworkManager on Slackware. I was just curious as to why this behavior occurs.

duryodhan · 01-09-2008, 08:23 PM

instead of running dhcpcd eth0 try running dhclient eth0.

I know this doesn't make much sense ,but many times I have seen dhclient solve a few problems caused by dhcpcd.

evilDagmar · 01-10-2008, 06:01 AM

Yo, pay attention.

He's using NetworkManager, which calls dhcdbd to do the work of handling leases, which in turn calls ISC's dhclient. NetworkManager does not nor can it invoke dhcpcd. I know there's a bit of alphabet soup going on here, but the details are important.

Before someone can even go "there", dhclient doesn't do anything particularly out of the ordinary (or differently from dhcpcd) when it makes it's query. Fire up tcpdump and check if you like. DHCP messages are blessedly short and easy to figure out when you're looking at the raw packet.