Subject: Re: Problems with bridge(4) and vlan(4)
To: Manuel Bouyer <bouyer@antioche.lip6.fr>
From: Martti Kuparinen <martti.kuparinen@iki.fi>
List: port-xen
Date: 04/29/2005 14:01:47
I was too fast to say "everything is okay". Now some of the domUs have
stopped responding to ping and it seems like ARP is not working
correctly. Here's my setup:

wm1 --> vlan1208 --> bridge1208 <-- xvif8.1

wm1         no address, running several VLANs in tagged mode
vlanNNNN    no address, one for each VLAN (NNNN=VLAN id)
bridgeNNNN  no address, one for each VLAN, connected to the
             corresponding vlanNNNN and xvifM.N
xennetN     These have the addresses I'm trying to reach


I started to ping from xxx.xxx.xxx.209 and at the same time I ran
tcpdump on xvif8.1, vlan1208 and xennet1.

I can see ARP coming all the way to the domU's xennet1 but domU (this
is running NetBSD 3.0_BETA) does not respond to ARP queries. Any
ideas why?

Martti

#################### domain 0 ###################
ROOT xen2:~> tcpdump -veni xvif8.1
13:30:27.173361 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209
13:30:28.173992 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209
13:30:29.183906 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209

ROOT xen2:~> tcpdump -veni vlan1208
13:30:27.173353 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209
13:30:28.173985 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209
13:30:29.183899 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209


ROOT xen2:~> ifconfig wm1
wm1: flags=8b43<UP,BROADCAST,RUNNING,PROMISC,ALLMULTI,SIMPLEX,MULTICAST> 
mtu 1500
         capabilities=87<IP4CSUM,TCP4CSUM,UDP4CSUM,TSO4>
         enabled=0
         address: 00:04:23:b4:e1:64
         media: Ethernet autoselect (100baseTX full-duplex)
         status: active
         inet6 fe80::204:23ff:feb4:e164%wm1 prefixlen 64 scopeid 0x2

ROOT xen2:~> ifconfig vlan1208
vlan1208: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 
1500
         vlan: 1208 parent: wm1
         address: 00:04:23:b4:e1:64
         inet6 fe80::204:23ff:feb4:e164%vlan1208 prefixlen 64 scopeid 0xc

ROOT xen2:~> ifconfig bridge1208
bridge1208: flags=41<UP,RUNNING> mtu 1500

ROOT xen2:~> ifconfig xvif8.1
xvif8.1: 
flags=8963<UP,BROADCAST,NOTRAILERS,RUNNING,PROMISC,SIMPLEX,MULTICAST> 
mtu 1500
         address: aa:00:00:1d:08:f3
         inet6 fe80::a800:ff:fe1d:8f3%xvif8.1 prefixlen 64 scopeid 0x32

#################################################

#################### domain U ###################
ROOT r210:~> tcpdump -veni xennet1
13:30:26.785704 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209
13:30:27.786305 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209
13:30:28.796207 00:04:23:ad:1c:c6 > ff:ff:ff:ff:ff:ff, ethertype ARP 
(0x0806), length 60: arp who-has xxx.xxx.xxx.210 tell xxx.xxx.xxx.209


ROOT r210:~> ifconfig xennet1
xennet1: flags=8863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST> 
mtu 1500
         address: aa:00:00:1c:08:f3
         inet xxx.xxx.xxx.210 netmask 0xfffffff8 broadcast xxx.xxx.xxx.215
         inet6 fe80::a800:ff:fe1c:8f3%xennet1 prefixlen 64 scopeid 0x3
#################################################