Disabling VLAN_HWTAGGING

[Ruslan Ermilov]

On Tue, Mar 30, 2004 at 11:19:00AM -0800, Jacob S. Barrett wrote:
> Now what have I done wrong.  I noticed this yesterday and I can't figure out 
> what I have done wrong.  VLAN tagged ARP requests coming into if_nge are not 
> visible anymore (tcpdump).  Non VLAN tagged ARP requests are visible.  Debug 
> statements are showing the frame doesn't make it into the driver.
> 
Like I said in another email in this thread, if NIC is doing VLAN
stripping in firmware, you won't be able to see the original VLAN
packet with tcpdump(8) in 5.x.  Instead, it will be shown an inner
Ethernet packet on the physical ("parentdev") interface.  This can
be fixed.  But neither 4.x nor 5.x will show you the virgin VLAN
packet on output if the NIC does VLAN insertion in firmware.

> This is the request as it leaves the remote host.
> 11:04:53.588726 0:90:27:f4:58:1d ff:ff:ff:ff:ff:ff 8100 46: 802.1Q vlan#2 P0 
> arp who-has 10.2.0.1 tell 10.2.0.2
> 
> Strangely though, other broadcasts that are VLAN tagged get delivered to the 
> driver. With your patch they now correctly show up on the ng_vlan interface 
> too.
> 
> This is the other broadcast as sent by remote host:
> 0:90:27:f4:58:1d ff:ff:ff:ff:ff:ff 8100 257: 802.1Q vlan#2 P0 10.2.0.2.138 > 
> 10.2.0.255.138: NBT UDP PACKET(138)
> 
> This is he above broadcast that was received by both if_nge and ng_vlan:
> 0:90:27:f4:58:1d ff:ff:ff:ff:ff:ff 0800 246: 10.2.0.2.138 > 10.2.0.255.138: 
> NBT UDP PACKET(138)
> 
> Any idea why the ARP packets would be filtered at the NIC?
> 
Hmm, this shouldn't happen.  Perhaps you have a firewall configured
to run at layer2 that rejects them?

> The same goes for 
> ARP replies.  I can ARP request from the if_nge machine, but the replies get 
> dropped.
> 
If you set ARP entries manually, can you ping each other?


Cheers,
-- 
Ruslan Ermilov
ru at FreeBSD.org
FreeBSD committer
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-net/attachments/20040330/cea986d2/attachment-0001.bin