Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 14 Jan 2003 07:00:16 -0800 (PST)
From:      Christoph Loibl <c@tix.at>
To:        freebsd-bugs@FreeBSD.org
Subject:   Re: kern/46961: bridging between vlan-interfaces on same trunk interface does not work
Message-ID:  <200301141500.h0EF0GMk027282@freefall.freebsd.org>

next in thread | raw e-mail | index | archive | help
The following reply was made to PR kern/46961; it has been noted by GNATS.

From: Christoph Loibl <c@tix.at>
To: FreeBSD-gnats-submit@FreeBSD.org
Cc:  
Subject: Re: kern/46961: bridging between vlan-interfaces on same trunk interface does not work
Date: Tue, 14 Jan 2003 15:58:36 +0100

 hi!
 
 On Tue, Jan 14, 2003 at 02:53:23PM +0100, Attila Nagy wrote:
 > 	briding beween vlan interfaces seems to be broken:
 > I don't know whether it's FreeBSD's bridge code, or your switch, but you
 > can try to disable STP (Spanning Tree Protocol) on the switch.
 > But prior to that you can see if it blocked the interface or not. There
 > are a lot of switches which has only one STP instance, not many, per
 > VLANs, so when you try to bridge between two VLANs it may think it is a
 > loop.
 
 i did some more debugging homework on that issue, and established a
 _very_simple_ setup using a ethernet-hub instead of the HP2524 switches:
 
 +---------+          +-----+
 | box 1   |----------|HUB  |
 +---------+          |     |   +---------------+
                      |     |---| box3 (bridge) |
 +---------+          |     |   +---------------+
 | box 2   |----------|     |
 +---------+          +-----+
 
 first i setup the 2 boxes (1,2) with vlan interfaces with the same vlanid to see if 
 communication over the vlan interfaces works. ([x] works fine - i didn't care about 
 using edX interfaces and didn't worry about mtu issues, as packets i transmit are 
 very small) 
 
 -> then i reconfigured the boxes 2 use different vlans and setup box 3 (communication 
 was tested the same way beween all devices)
 
 the final vlan-bridge setup was:
 
 on box 1 i have: 
 
 vlan0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1496
         inet 192.168.17.10 netmask 0xffffff00 broadcast 192.168.17.255
         inet6 fe80::204:76ff:fe0c:2b2%vlan0 prefixlen 64 scopeid 0x10
         ether 00:4f:4c:04:39:76
         vlan: 20 parent interface: ed1
 
 on box 2:
 
 vlan1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1496
         inet 192.168.17.3 netmask 0xffffff00 broadcast 192.168.17.255
         inet6 fe80::210:60ff:fe80:9733%vlan1 prefixlen 64 scopeid 0x9
         ether 00:10:60:80:97:33
         vlan: 21 parent interface: ed0
 
 the bridge has:
 
 vlan0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1496
         inet6 fe80::250:4ff:fe65:a725%vlan0 prefixlen 64 scopeid 0x4
         ether 00:50:04:65:a7:25
         vlan: 21 parent interface: xl0
 
 vlan1: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1496
         inet6 fe80::250:4ff:fe65:a725%vlan1 prefixlen 64 scopeid 0x5
         ether 00:50:04:65:a7:25
         vlan: 20 parent interface: xl0
 
 net.link.ether.bridge_cfg: vlan0,vlan1
 net.link.ether.bridge: 1
 net.link.ether.bridge_ipfw: 0
 net.link.ether.bridge_ipf: 0
 net.link.ether.bridge_ipfw_drop: 0
 net.link.ether.bridge_ipfw_collisions: 0
 
 
 start to ping box2 at box1: 
 
 on vlan20:
 arp-request for 192.168.17.3 as broadcast
 
 on vlan21:
 bridged arp-request for 192.168.17.3 as broadcast
 arp-answer from 192.168.17.3 to 192.168.17.10 _no_broadcast
 
 --> this can only be seen if watching with tcpdump on xl0. 
 using "tcpdump -nei vlan0" does not report any traffic at all(?!).
 
 if you need more information i may repeat this setup and provide you with a login 
 to 2 of the testboxes.
 
 best regards
 
 christoph loibl
 
 -- 
 CHRISTOPH LOIBL >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
 mailto:c@tix.at.    |                         "Penguins are tasty snacks"
 http://pix.tix.at   |                                   from freebsd docu
 CHL-RIPE >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> PGP-Key-ID: 0x4B2C0055 >>>

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-bugs" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200301141500.h0EF0GMk027282>