WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-users

[Xen-users] Trouble with Xen networking

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-users] Trouble with Xen networking
From: "Erik G. Burrows" <erik@xxxxxxxxxxxxxxx>
Date: Mon, 19 Jul 2010 14:50:31 -0700 (PDT)
Delivery-date: Mon, 19 Jul 2010 14:51:36 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
Importance: Normal
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: SquirrelMail/1.4.15
All,
I'd appreciate help diagnosing the following problem I'm having getting
networking under Xen working.

First, I have this exact same setup working on other types of hosts, so
something specific to this type of host, Appro S1321, is causing the
problem. Also, I have tried it on three different hosts of this same
model, with the exact same results.

So, here's the setup:
  Appro S1321 host
  32GB RAM
  2x AMD Opteron 285
  2x Broadcom BCM5721 NICs (tg3 driver in dom0)
  OS: OVM Server v. 2.2.1
  Xen 3.4.0

When booting the system clean, the interfaces and routes look like this:
eth0      Link encap:Ethernet  HWaddr 00:D0:68:10:00:D1
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:248 errors:0 dropped:0 overruns:0 frame:0
          TX packets:247 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:41596 (40.6 KiB)  TX bytes:32460 (31.6 KiB)
          Interrupt:21

eth1      Link encap:Ethernet  HWaddr 00:D0:68:10:00:D0
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
          Interrupt:22

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:166 errors:0 dropped:0 overruns:0 frame:0
          TX packets:166 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:20533 (20.0 KiB)  TX bytes:20533 (20.0 KiB)

xenbr0    Link encap:Ethernet  HWaddr 00:D0:68:10:00:D1
          inet addr:10.12.12.110  Bcast:0.0.0.0  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:315 errors:0 dropped:0 overruns:0 frame:0
          TX packets:317 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:52156 (50.9 KiB)  TX bytes:39120 (38.2 KiB)

xenbr1    Link encap:Ethernet  HWaddr 00:D0:68:10:00:D0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)


Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.12.12.0      0.0.0.0         255.255.255.0   U     0      0        0
xenbr0
0.0.0.0         10.12.12.1      0.0.0.0         UG    0      0        0
xenbr0


When I start a guest, it creates vif1.0, as:

vif1.0    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:1156 overruns:0 carrier:0
          collisions:0 txqueuelen:32
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

And adds the vif to the bridge:

bridge name     bridge id               STP enabled     interfaces
xenbr0          8000.00d0681000d1       no              vif1.0
                                                        eth0
xenbr1          8000.00d0681000d0       no              eth1

The problem, is that the dom0 OS can ping/otherwise-connect-to the domU,
and visa-versa, but the domU cannot get to the outside world.

If I try to ping the domU from another host on the same subnet (on a dumb
switch, nothing fancy), I get no response at all.

Tcpdumping eth0/xenbr0 on dom0 doesn't even show the icmp requests coming
in. I have run "ifconfig eth0 promisc", and this does not help.

On a fancier switch, I spanned the system's network port to another host,
and ran tcpdump on that. From there, I can see the ICMP requests coming
in, so I know it's not some MAC-table mix-up on the switch.

If, before starting the guest VM, I run "/etc/init.d/network restart",
then start the guest, networking will actually work for it, for a short
time (~1 min). All I can see that this accomplishes is shutting down the
eth1 nic, and assigning the xenbr0 IP address to eth0. If I do this
manually, nothing useful happens.

Any ideas? As I said before, I have this exact same software setup working
on other machine types. Even the same VM image will work on another
machine...

Thanks,
  Erik Burrows



-- 
If you are flammable and have legs, you're never blocking a fire exit.
-Mitch Hedberg


_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-users] Trouble with Xen networking, Erik G. Burrows <=