Bug 175053 – dhcpcd-3.0.16-r1 does not set a default gateway

• Product: Gentoo Linux
• Status: VERIFIED INVALID

[Description Syed Amer Gilani 2007-04-18 09:43:36 UTC]

In my local Network the IP addresses are assigned by net-dns/dnsmasq-2.31 on an amd64 server.

After updating dhcpcd to 3.0.16-r1 i dont get a default gw from the dhcp server, only static routes:

[root:/] dhcpcd -k eth0
[root:/] dhcpcd -d eth0
Info, eth0: dhcpcd 3.0.17 starting
Info, eth0: hardware address = 00:02:3f:15:91:fa
Info, eth0: broadcasting for a lease
Debug, eth0: sending DHCP_DISCOVER with xid 0x4a83a5cd
Debug, eth0: waiting on select for 20 seconds
Debug, eth0: waiting on select for 20 seconds
Debug, eth0: waiting on select for 20 seconds
Debug, eth0: got a packet with xid 0x4a83a5cd
Info, eth0: offered 192.168.1.34 from 192.168.1.253
Debug, eth0: sending DHCP_REQUEST with xid 0x4a83a5cd
Debug, eth0: waiting on select for 18 seconds
Debug, eth0: got a packet with xid 0x4a83a5cd
Info, eth0: leased 192.168.1.34 for 43200 seconds
Debug, eth0: renew in 21600 seconds
Debug, eth0: rebind in 37800 seconds
Info, eth0: adding IP address 192.168.1.34/24
Info, eth0: adding route to 10.8.0.0 (255.255.255.0) via 192.168.1.252 metric 0
Debug, eth0: writing /etc/resolv.conf
Debug, eth0: /etc/ntp.conf already configured, skipping
Debug, eth0: /etc/ntpd.conf already configured, skipping
Debug, eth0: writing /var/lib/dhcpcd/dhcpcd-eth0.info
Debug, eth0: forking to background
[root:/] route
Kernel IP Routentabelle
Ziel            Router          Genmask         Flags Metric Ref    Use Iface
10.8.0.0        eriwan.systec   255.255.255.0   UG    0      0        0 eth0
192.168.1.0     *               255.255.255.0   U     0      0        0 eth0
loopback        *               255.0.0.0       U     0      0        0 lo

With dhcpcd-2.0.5-r1 i get the default route:
[root:/] dhcpcd -k eth0
[root:/] dhcpcd -d eth0
Info, MAC address = 00:02:3f:15:91:fa
Debug, broadcasting DHCP_REQUEST for 192.168.1.34
Debug, timed out waiting for DHCP_ACK response
Debug, broadcasting DHCP_DISCOVER
Debug, dhcpIPaddrLeaseTime=43200 in DHCP server response.
Debug, DHCP_OFFER received from  (192.168.1.253)
Debug, broadcasting DHCP_REQUEST for 192.168.1.34
Debug, dhcpIPaddrLeaseTime=43200 in DHCP server response.
Debug, DHCP_ACK received from  (192.168.1.253)
Debug, broadcasting ARPOP_REQUEST for 192.168.1.34
Info, verified 192.168.1.34 address is not in use
Info, your IP address = 192.168.1.34
Debug, orig hostname = AmerLap
[root:/] route -n
Kernel IP Routentabelle
Ziel            Router          Genmask         Flags Metric Ref    Use Iface
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
0.0.0.0         192.168.1.254   0.0.0.0         UG    0      0        0 eth0


Reproducible: Always

Steps to Reproduce:

[Comment 1 Christian Heim (RETIRED) 2007-04-18 10:24:27 UTC]

*** This bug has been marked as a duplicate of bug 173931 ***

[Comment 2 Syed Amer Gilani 2007-04-18 10:30:39 UTC]

this is not an duplicate of 173931. there the gateway is unreachable. here it is but dhcpcd is not even trying to set it.

[Comment 3 Roy Marples (RETIRED) 2007-04-18 10:35:27 UTC]

If you feel this is not a duplicate, then please attach a whireshark trace of dhcpcd-3.x and dhcpcd-2.x of the dhcp transaction and then re-open this bug.

Thanks

[Comment 4 Syed Amer Gilani 2007-04-18 12:51:11 UTC]

Created attachment 116632 [details]
dhcpcd 2.0.5 Wireshark dump

[Comment 5 Syed Amer Gilani 2007-04-18 12:51:30 UTC]

Created attachment 116633 [details]
dhcpcd 3.0.16 Wireshark dump

[Comment 6 Syed Amer Gilani 2007-04-18 12:55:45 UTC]

It seems that 3.0.16 does not request any special informations in the DHCP Discover, but 2.0.5 does. And the default answer from dnsmasq does not contain the router entry.

[Comment 7 Roy Marples (RETIRED) 2007-04-18 19:56:55 UTC]

You've set Classless Static Routes on the DHCP server.
This overrides any static routes *and* routers provided. You need to include your default route in your CSR option.



See RFC3442 - DHCP Client Behaviour

   If the DHCP server returns both a Classless Static Routes option and
   a Router option, the DHCP client MUST ignore the Router option.

   Similarly, if the DHCP server returns both a Classless Static Routes
   option and a Static Routes option, the DHCP client MUST ignore the
   Static Routes option.

[Comment 8 Syed Amer Gilani 2007-04-19 08:20:28 UTC]

setting the default route as a classless static route solved the problem. 
but this seems to be a DHCP Behaviour that no other DHCP client cares about. We have here many  Windows xp/98/2000, apple and linux workstations which worked normal with the previous DHCP server settings.
but thanks anyway.

[Comment 9 Roy Marples (RETIRED) 2007-04-19 08:32:04 UTC]

(In reply to comment #8)
> setting the default route as a classless static route solved the problem. 
> but this seems to be a DHCP Behaviour that no other DHCP client cares about. We
> have here many  Windows xp/98/2000, apple and linux workstations which worked
> normal with the previous DHCP server settings.
> but thanks anyway.

Only clients that understand CSR's would behave correctly. Of that list, only windows 2000 and XP should know about CSR's. dhcpcd-3 is the only linux client that knows about CSR's

dhclient from FreeBSD also knows and behaves in the same manner as dhcpcd-3, so I would assume that the Microsoft clients don't follow the RFC exactly, which should not come as a suprise.