NetBSD-Users archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: dhcpcd failure



On 21/02/2019 14:58, triaxx wrote:
Le 2019-01-18 17:54, Andy Ruhl a écrit :
On Fri, Jan 18, 2019 at 2:09 AM Roy Marples <roy%marples.name@localhost> wrote:

Hi Fred

On 18/01/2019 06:05, triaxx wrote:
> I experienced a dhcpcd that cannot connect to a Cisco gateway through a
> fresh NetBSD 8.0. I tried dhclient which succeed.
>
> I didn't see relevant diff between MAIN and netbsd-8.
>
> I would like to send a PR but I'm interesting to know what informations
> could be relevant/helping.

You could try editing /etc/dhcpcd.conf and commenting out duid and using
clientid. If that still fails, try commenting out both.

If either work, complain to Cisco about their lack of RFC compliance.
Regardless, let me know the outcome please.

If it really is a Cisco compliance issue, I'd like to see a wireshark
of the failing request and the successful one for my own amusement.
This command seems to work on my mac, I'm guessing it will be similar
on NetBSD except the interface name:

tshark -i en0 -f "udp port 67 or 68" -w dhcp.pcap

Andy

tcpdump is like the observer of the Schrödinger's cat, it interfere in measurement.

If I run tcpdump -i re0 "udp port 67 or 68" -w dhcpcd.pcap when running service -v dhcpcd restart, it works fine...

Then, I can just provide the packet trace when the request succeed:

14:56:43.981194 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 80:ee:73:c1:cd:36 (oui Unknown), length 318 14:56:44.019208 IP 192.168.0.1.bootps > 192.168.0.11.bootpc: BOOTP/DHCP, Reply, length 548 14:56:44.019338 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 80:ee:73:c1:cd:36 (oui Unknown), length 325 14:56:44.079055 IP 192.168.0.1.bootps > 192.168.0.11.bootpc: BOOTP/DHCP, Reply, length 548 14:56:53.955162 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 80:ee:73:c1:cd:36 (oui Unknown), length 319 14:56:53.988890 IP 192.168.0.1.bootps > 192.168.0.11.bootpc: BOOTP/DHCP, Reply, length 548

Looks to me like the DHCP client is broadcasting for a lease (ie it doesn't have an IP address) but the DHCP server thinks it has an IP address and is unicasting to something that doesn't exist?

Can you add more -vvvv to see if the client is giving any hints if it has an ip address?

Roy


Home | Main Index | Thread Index | Old Index