802.1q question

Hi,

I'm trying to understand the 802.1q vlan working. I tried to setup a
little lab environment but I cant get the thing started.

I have to laptops, both running Debian. I have a Cisco catalyst switch.

First on the Cisco I do the following:

Configure terminal
Interface fastethernet 0/7
Switchport trunk encapsulation dot1q
Switchport trunk allowed vlan 666
Switchport mode trunk

The same for fastethernet 0/8

Then on the linux boxes:

ifconfig eth0 down
ifconfig eth0 0.0.0.0 up
modprobe 8021q
vconfig add eth0 666
ifconfig eth0.666 192.168.1.1 netmask 255.255.255.0 broadcast
192.168.1.255 up

And on the other box I do the same except I use 192.168.1.2 in stead of
192.168.1.1 .

Then the big test ping 192.168.1.2 from the 192.168.1.1 machine and
...... nope, nothing happens.

While looking at this issue I used ethereal to see what is actually going
over the line. And from the two debian boxes I miss the 802.1q headers in
the TCP package. In the documentation and when I look at the traffic from
a Cisco IP-phone I see that they are sending some VLAN information into 4
bytes but my linux boxes don’t do that.

What is wrong?

The switch is a clean installation, just default only the things changed I
mentioned above. The network itself without Vlan is working. Rebooted
everything at least a dozen time till now.

Thx.

CU

Roel