Ubuntu
dhcp3 package

  1. Bug #295520
  2. Comment #5

Comment 5 for bug 295520

Revision history for this message
gsupport (support-gatsby) wrote :

DistroRelease: Ubuntu 9.10
Package: dhcp3-server 3.1.2-1ubuntu7.1
PackageArchitecture: amd64
ProcVersionSignature: Ubuntu 2.6.31-19.56-server

I can confirm that even with the recent configuration above any DHCP requests that come over a tagged VLAN are also seen by the untagged interface. Here is a sample request coming over VLAN 5;

DHCPDISCOVER from 00:23:8b:27:06:8b via eth1
DHCPDISCOVER from 00:23:8b:27:06:8b via eth1.5
DHCPOFFER on 192.168.213.152 to 00:23:8b:27:06:8b via eth1
DHCPOFFER on 192.168.205.150 to 00:23:8b:27:06:8b via eth1.5

In case there is any doubt;

#> grep VID /proc/net/vlan/eth1.5
eth1.5 VID: 5 REORDER_HDR: 1 dev->priv_flags: 1

The DHCP server still sees the tagged VLAN packets when the VLAN interface isn't listed in INTERFACES.

#> dhcpd3 -d eth1
...
Listening on LPF/eth1/00:04:23:ab:3e:ea/192.168.213/24
Sending on LPF/eth1/00:04:23:ab:3e:ea/192.168.213/24
Sending on Socket/fallback/fallback-net
DHCPDISCOVER from 00:23:8b:27:06:8b via eth1
DHCPOFFER on 192.168.213.152 to 00:23:8b:27:06:8b via eth1

Naturally, the device doesn't see the offer as it is going out on the untagged VLAN.