Re: xen and networking problems

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Thu, Oct 29, 2009 at 09:48:17PM -0600, Brook Milligan wrote:
> Now that I have gotten a xen kernel to boot (thanks!)[1], I am having
> trouble with the network interface under xen.  In short, the kernel
> boots and apparently configures the interface, but no packets can be
> transmitted.  The identical configuration works fine with a MONOLITHIC
> kernel compiled from current source as of 2009-08-01 (which is the
> same as for the xen kernel and the entire system).
> 
> When booted with 64Mb (of a total 16Gb) of RAM for dom0, the
> XEN3PAE_DOM0 kernel probes the network interfaces as follows:
> 
>      fxp0 at pci7 dev 2 function 0: i82550 Ethernet, rev 13
>      ioapic0: int17 
> 0x1a9c0<vector=0xc0,delmode=0x1,logical,actlo,level,masked,dest=0x0> 
> 0xf000000<target=0xf>
>      fxp0: interrupting at ioapic0 pin 17, event channel 6
>      fxp0: Ethernet address 00:30:48:23:3a:81
>      inphy0 at fxp0 phy 1: i82555 10/100 media interface, rev. 4
>      inphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
>      fxp1 at pci7 dev 3 function 0: i82550 Ethernet, rev 13
>      fxp1: interrupting at ioapic0 pin 18, event channel 5
>      xen_alloc_contig: XENMEM_decrease_reservation failed!
>      fxp1: unable to allocate control data, error = 12
> 
> Note the error with the second interface.  When booted with either
> 256Mb or 1024Mb of RAM the same error shows up, but for both network
> interfaces.
> 
> The one physical interface is configured as follows:
> 
>      # ifconfig.fxp0
>      media autoselect
>      inet 172.16.0.2/24
> 
> and a bridge is configured as follows for later use by domUs:
> 
>      # ifconfig.bridge0
>      create
>      !brconfig $int add fxp0
>      !brconfig $int stp fxp0
>      !brconfig $int up
> 
> 'ifconfig -a' reports the following (which is essentially identical,
> barring the missing fxp1 interface, to the report when running
> successfully under the MONOLITHIC kernel):
> 
>      fxp0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
>            
> capabilities=3f00<IP4CSUM_Rx,IP4CSUM_Tx,TCP4CSUM_Rx,TCP4CSUM_Tx,UDP4CSUM_Rx,UDP4CSUM_Tx>
>            enabled=0
>            address: 00:30:48:23:3a:81
>            media: Ethernet autoselect (100baseTX full-duplex)
>            status: active
>            inet 172.16.0.2 netmask 0xffffff00 broadcast 172.16.0.255
>            inet6 fe80::230:48ff:fe23:3a81%fxp0 prefixlen 64 scopeid 0x1
>      lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 33184
>            inet 127.0.0.1 netmask 0xff000000
>            inet6 ::1 prefixlen 128
>            inet6 fe80::1%lo0 prefixlen 64 scopeid 0x2
>      bridge0: flags=41<UP,RUNNING> mtu 1500
> 
> However, no packets can be transmitted.  For example, ping reports
> 'host is down' errors.

Please check with netstat if you have interrupt for this device.
You could also run tcpdump and see if you receive some packets.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--