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I have a LAN and i need to create a LAB with three VLAN on my boxes, Linux and FreeBSD.

Well i create a VLAN 1 on the linux box as follow:

sudo vconfig add eth0 1
sudo ifconfig eth0.1 inet6 add 2001:470:9b36:2::2/64

and i do the same on the FreeBSD box:

sudo ifconfig vlan1 create
sudo ifconfig vlan1 inet6 2001:470:9b36:2::1 prefixlen 64 vlan 1 vlandev bge0

ifconfig of FreeBSD box

vlan2: flags=8843 metric 0 mtu 1500
    ether 00:11:85:61:90:f2
    inet6 fe80::211:85ff:fe61:90f2%vlan2 prefixlen 64 scopeid 0x5 
    inet6 2001:470:9b36:2::1 prefixlen 64 
    inet netmask 0xffffff00 broadcast
    nd6 options=3
    media: Ethernet autoselect (100baseTX )
    status: active
    vlan: 2 parent interface: bge0

and the ifconfig of the Linux Box:

eth0.2    Link encap:Ethernet  HWaddr d8:d3:85:28:d3:28
inet addr: Bcast: Mask: inet6 addr: fe80::dad3:85ff:fe28:d328/64 Scope:Link inet6 addr: 2001:470:9b36:2::2/64 Scope:Global UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:962 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 B) TX bytes:43400 (42.3 KiB)

But i still not able to ping the VLANs from each side ? What would be the states of each of the interfaces bge0 and eth0 ?

NB: the eth0 and bge0 are up and running

share|improve this question
Is vlan1 on FreeBSD up? – jkj Jun 25 '11 at 19:42
the two vlans are up and running – mezgani Jun 25 '11 at 19:47
Can both ends ping their own VLAN ip? Next I'd see if the traffic shows on the other end with tcpdump -evni bge0 / eth0 – jkj Jun 25 '11 at 19:54
In the both side i see "neighbor solicitation, who has" request – mezgani Jun 25 '11 at 20:13
Is the whohas request answerred? Does ndp -a on FreeBSD or ip neigh show on Linux show the other end's MAC? – jkj Jun 27 '11 at 9:16

Have you tried something other then VLAN1? VLAN1 is typically considered to be the un-tagged VLAN. Generally you should not be trying to add that as a tagged VLAN.

I am not sure about FreeBSD, but in Linux, there is a warning when you try to use that.

How are the two systems physically connected?

share|improve this answer
they are connected using an Ethernet switch Netgear, i think that even i use other VLAN the problem still there – mezgani Jun 26 '11 at 7:41
Is it a managed switched or unmanaged? Which model? – Rilindo Jun 27 '11 at 19:08
an unmanaged netgear ethernet switch – mezgani Jun 27 '11 at 19:41

If all you see is the 'who has' requests, there is no ethernet traffic on the chosen vlan. A switch with vlan or jumbo frame support may be needed, although I'm not sure about this (neighbour discovery and icmp6 traffic shouldn't use 1500 byte frames).

Could you post the output of 'ifconfig -a' on both systems? My guess is something is missing.

share|improve this answer

You'll need a Layer 2 switch that will support 802.1Q. Effectively, that would mean a managed switch. On an unmanaged switch, there is no mechanism for the frame to be routed based on the tag.

share|improve this answer
-1 No, a switch that is not 802.1q aware will simply pass the packet along without consideration for the vlan tag. – Chris S Jun 27 '11 at 20:52
+1 right, no need to – mezgani Jun 27 '11 at 22:42
Fair enough. I probably need to review how VLAN should work, then. – Rilindo Jun 27 '11 at 23:26

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