thr3ads.net - Xen users - [Xen-users] Dom0 Crash - High Network Load

If this information is useful, please help other people find it:
Share via:

Thaddeus Hogan

2009-Nov-05 16:01 UTC

[Xen-users] Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1

I''m looking for a place to start with a problem I am having where I
think
high network load is crashing my Xen host. Any help you can offer is
greatly appreciated! 

I started having an issue with my dom0 crashing when under very high
network load. I discovered this when I ran a large backup (1.7 TB) on a
domU. 

I ran the backup with my Bacula setup that I have been using for over a
year. The client is a domU. The dom0 on that host is running the Bacula
storage daemon, which accepts data for backup over the network and writes
it to some locally attached device. In my case the dom0 has two eSATA
attached drives that are used for backups and all domUs on that host write
their backups over the network to that storage. 

When I ran the backup I was sustaining about 500mbit from the domU to the
dom0. After 4.5 hours Nagios reported that the whole host and all domUs had
dropped off the network. When I looked at the console on the host it was
hung, the screen was blank, and I couldn''t backscroll or see any
console
messages. 

The next day I tried the backup again. I was sustaining about 500mbit of
network traffic from the DomU to the dom0 again, and after 45 minutes the
host crashed. I had the console already connected to a KVM and was able to
look at it immediately. Again the screen was blank and there were no
console messages accessible. 

So, here is the setup: 

The Xen host is a Debian Lenny system running Xen 3.2-1:
vast:~# uname -a
Linux vast 2.6.26-2-xen-amd64 #1 SMP Fri May 29 00:30:34 UTC 2009 x86_64
GNU/Linux

This host is on consumer grade hardware, an AMD Athlon x2 4450e on a board
with an AMD SB700/SM800 chipset. 

PCI manifest: 

00:00.0 Host bridge: ATI Technologies Inc RX780/RX790 Chipset Host Bridge 
00:02.0 PCI bridge: ATI Technologies Inc RD790 PCI to PCI bridge (external
gfx0 port A) 
00:09.0 PCI bridge: ATI Technologies Inc RD790 PCI to PCI bridge (PCI
express gpp port E) 
00:0a.0 PCI bridge: ATI Technologies Inc RD790 PCI to PCI bridge (PCI
express gpp port F) 
00:11.0 SATA controller: ATI Technologies Inc SB700/SB800 SATA Controller
[AHCI mode] 
00:12.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0
Controller 
00:12.1 USB Controller: ATI Technologies Inc SB700 USB OHCI1 Controller 
00:12.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI
Controller
00:13.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0
Controller 
00:13.1 USB Controller: ATI Technologies Inc SB700 USB OHCI1 Controller 
00:13.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI
Controller 
00:14.0 SMBus: ATI Technologies Inc SBx00 SMBus Controller (rev 3a) 
00:14.1 IDE interface: ATI Technologies Inc SB700/SB800 IDE Controller 
00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA) 
00:14.3 ISA bridge: ATI Technologies Inc SB700/SB800 LPC host controller 
00:14.4 PCI bridge: ATI Technologies Inc SBx00 PCI to PCI Bridge 
00:14.5 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI2
Controller 
00:18.0 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron]
HyperTransport Technology Configuration 
00:18.1 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron]
Address Map 
00:18.2 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron]
DRAM Controller 
00:18.3 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron]
Miscellaneous Control 
01:00.0 VGA compatible controller: nVidia Corporation G72 [GeForce 7300
SE] (rev a1) 
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B
PCI Express Gigabit Ethernet controller (rev 01) 
03:00.0 SATA controller: JMicron Technologies, Inc. JMicron 20360/20363
AHCI Controller (rev 03) 
03:00.1 IDE interface: JMicron Technologies, Inc. JMicron 20360/20363 AHCI
Controller (rev 03) 
04:05.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8169
Gigabit Ethernet (rev 10)

Networking Configuration:

Notes: br0 is an internal VLAN.  DomUs are bridged to it as well as a
physical network connection.

vast:~# ifconfig -a
br0       Link encap:Ethernet  HWaddr 00:1f:e2:0a:e3:05
          inet addr:192.168.1.3  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::21f:e2ff:fe0a:e305/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:451568 errors:0 dropped:0 overruns:0 frame:0
          TX packets:235845 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:92830085 (88.5 MiB)  TX bytes:44937509 (42.8 MiB)

br1       Link encap:Ethernet  HWaddr 00:1e:2a:cc:60:c5
          inet6 addr: fe80::21e:2aff:fecc:60c5/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:3897027 errors:0 dropped:0 overruns:0 frame:0
          TX packets:6 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:193067739 (184.1 MiB)  TX bytes:468 (468.0 B)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:13725 errors:0 dropped:0 overruns:0 frame:0
          TX packets:13725 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:833520 (813.9 KiB)  TX bytes:833520 (813.9 KiB)

peth0     Link encap:Ethernet  HWaddr 00:1f:e2:0a:e3:05
          inet6 addr: fe80::21f:e2ff:fe0a:e305/64 Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:5924446 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8362451 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1496704915 (1.3 GiB)  TX bytes:9190427081 (8.5 GiB)
          Interrupt:17 Base address:0xc000

peth1     Link encap:Ethernet  HWaddr 00:1e:2a:cc:60:c5
          inet6 addr: fe80::21e:2aff:fecc:60c5/64 Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:15374016 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8330546 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:12532694766 (11.6 GiB)  TX bytes:1340211710 (1.2 GiB)
          Interrupt:20 Base address:0xec00

veth0     Link encap:Ethernet  HWaddr 00:00:00:00:00:00
          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:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

veth1     Link encap:Ethernet  HWaddr 00:00:00:00:00:00
          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:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

veth2     Link encap:Ethernet  HWaddr 00:00:00:00:00:00
          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:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

veth3     Link encap:Ethernet  HWaddr 00:00:00:00:00:00
          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:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

vif0.0    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          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:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

vif0.1    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          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:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

vif0.2    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          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:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

vif0.3    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          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:0
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

vif1.0    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:8227355 errors:0 dropped:0 overruns:0 frame:0
          TX packets:15373213 errors:0 dropped:110 overruns:0 carrier:0
          collisions:0 txqueuelen:32
          RX bytes:1202074959 (1.1 GiB)  TX bytes:12531316572 (11.6 GiB)

vif1.1    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:11546727 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8314451 errors:0 dropped:48 overruns:0 carrier:0
          collisions:0 txqueuelen:32
          RX bytes:12080578087 (11.2 GiB)  TX bytes:1308547773 (1.2 GiB)

vif2.0    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:2172180 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3769946 errors:0 dropped:25 overruns:0 carrier:0
          collisions:0 txqueuelen:32
          RX bytes:1366566815 (1.2 GiB)  TX bytes:4641322133 (4.3 GiB)

vif3.0    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:171483 errors:0 dropped:0 overruns:0 frame:0
          TX packets:384392 errors:0 dropped:57 overruns:0 carrier:0
          collisions:0 txqueuelen:32
          RX bytes:24409539 (23.2 MiB)  TX bytes:80670352 (76.9 MiB)

vif4.0    Link encap:Ethernet  HWaddr fe:ff:ff:ff:ff:ff
          inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:1930732 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2111307 errors:0 dropped:64 overruns:0 carrier:0
          collisions:0 txqueuelen:32
          RX bytes:291907043 (278.3 MiB)  TX bytes:422220590 (402.6 MiB)

Backup client domU configuration:

vast:~# cat /etc/xen/vm_store.cfg
name = ''store''
kernel = ''/vm/vmboot/u904_64/vmlinuz-2.6.28-15-server''
ramdisk = ''/vm/vmboot/u904_64/initrd.img-2.6.28-15-server''
root = ''/dev/xvda ro''

vcpus = 1
memory = 1024
disk = [ ''phy:/dev/sysvg/vm_store_root,xvda,w'',
        ''phy:/dev/sysvg/vm_store_swap,xvdb,w'',
        ''phy:/dev/datavg/datalv,xvdc,w'',
        ''phy:/dev/sysvg/bananaw7lv,xvde,w'' ]
vif = [ ''bridge=br0,mac=00:16:3e:00:00:01'' ]

on_shutdown = ''destroy''
on_reboot = ''restart''
on_crash = ''rename-restart''

Dom0 Module List:

vast:~# lsmod
Module                  Size  Used by
nf_conntrack_ipv4      19352  2
xt_state                6656  2
nf_conntrack           71440  2 nf_conntrack_ipv4,xt_state
xt_physdev              6928  6
iptable_filter          7424  1
ip_tables              21264  1 iptable_filter
x_tables               25096  3 xt_state,xt_physdev,ip_tables
bridge                 53800  0
netloop                 9088  0
crc32c                  6400  0
libcrc32c               7168  1 crc32c
ipv6                  289352  22
ib_iser                34296  0
rdma_cm                31860  1 ib_iser
ib_cm                  41512  1 rdma_cm
iw_cm                  13448  1 rdma_cm
ib_sa                  25344  2 rdma_cm,ib_cm
ib_mad                 39208  2 ib_cm,ib_sa
ib_core                59392  6 ib_iser,rdma_cm,ib_cm,iw_cm,ib_sa,ib_mad
ib_addr                10888  1 rdma_cm
iscsi_tcp              21764  0
libiscsi               32768  2 ib_iser,iscsi_tcp
scsi_transport_iscsi    36256  4 ib_iser,iscsi_tcp,libiscsi
fuse                   54464  1
loop                   19724  0
serio_raw               9860  0
psmouse                42396  0
parport_pc             31016  0
parport                42416  1 parport_pc
pcspkr                  7040  0
k8temp                  9088  0
snd_hda_intel         436824  0
snd_pcm                83720  1 snd_hda_intel
snd_timer              26640  1 snd_pcm
snd                    64072  3 snd_hda_intel,snd_pcm,snd_timer
soundcore              12192  1 snd
snd_page_alloc         13072  2 snd_hda_intel,snd_pcm
i2c_piix4              13072  0
i2c_core               27936  1 i2c_piix4
button                 11680  0
evdev                  14592  0
ext3                  125328  5
jbd                    54568  1 ext3
mbcache                13188  1 ext3
dm_mirror              21120  0
dm_log                 14212  1 dm_mirror
dm_snapshot            19400  2
dm_mod                 59376  49 dm_mirror,dm_log,dm_snapshot
raid456               127008  1
async_xor               8448  1 raid456
async_memcpy            6912  1 raid456
async_tx               11764  3 raid456,async_xor,async_memcpy
xor                    10384  2 raid456,async_xor
raid1                  24576  1
md_mod                 81700  4 raid456,raid1
ide_cd_mod             36360  0
cdrom                  37928  1 ide_cd_mod
ide_disk               16640  6
sd_mod                 29376  8
atiixp                  8324  0 [permanent]
jmicron                 6912  0 [permanent]
ide_pci_generic         9220  0 [permanent]
ide_core              129308  5
ide_cd_mod,ide_disk,atiixp,jmicron,ide_pci_generic
ehci_hcd               36492  0
ata_generic            10116  0
ahci                   33164  4
ohci_hcd               25732  0
libata                165728  2 ata_generic,ahci
scsi_mod              161272  6
ib_iser,iscsi_tcp,libiscsi,scsi_transport_iscsi,sd_mod,libata
dock                   14240  1 libata
r8169                  31748  0
thermal                22816  0
processor              42436  1 thermal
fan                     9352  0
thermal_sys            17728  3 thermal,processor,fan


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

Pasi Kärkkäinen

2009-Nov-05 18:35 UTC

head link

Re: [Xen-users] Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1

On Thu, Nov 05, 2009 at 10:01:37AM -0600, Thaddeus Hogan
wrote:> 
> I''m looking for a place to start with a problem I am having where
I think
> high network load is crashing my Xen host. Any help you can offer is
> greatly appreciated! 
> 
> I started having an issue with my dom0 crashing when under very high
> network load. I discovered this when I ran a large backup (1.7 TB) on a
> domU. 
> 
> I ran the backup with my Bacula setup that I have been using for over a
> year. The client is a domU. The dom0 on that host is running the Bacula
> storage daemon, which accepts data for backup over the network and writes
> it to some locally attached device. In my case the dom0 has two eSATA
> attached drives that are used for backups and all domUs on that host write
> their backups over the network to that storage. 
> 
> When I ran the backup I was sustaining about 500mbit from the domU to the
> dom0. After 4.5 hours Nagios reported that the whole host and all domUs had
> dropped off the network. When I looked at the console on the host it was
> hung, the screen was blank, and I couldn''t backscroll or see any
console
> messages. 
> 
> The next day I tried the backup again. I was sustaining about 500mbit of
> network traffic from the DomU to the dom0 again, and after 45 minutes the
> host crashed. I had the console already connected to a KVM and was able to
> look at it immediately. Again the screen was blank and there were no
> console messages accessible. 
> 
Set up a serial console so you can capture the (error/crash) messages..

-- Pasi



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

Andrea Janna

2010-Feb-12 22:06 UTC

head link

Re: [Xen-users] Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1

-------- Original message --------
From: Thaddeus Hogan <thaddeus@thogan.com>
Date: 05/11/2009 17.01> I''m looking for a place to start with a problem I am having where
I think
> high network load is crashing my Xen host. Any help you can offer is
> greatly appreciated!
>
> I started having an issue with my dom0 crashing when under very high
> network load. I discovered this when I ran a large backup (1.7 TB) on a
> domU.
>    
I had a similar problem last month. I''m running a Debian Lenny dom0
with
3 Lenny domUs. Kernel 2.6.26 and all software packages are Lenny releases.
I use Bacula for backups on a DAT 72 tape device. Dom0 is running Bacula 
storage daemon, which manage the DAT device itself.
If I run a domU backup (Bacula file daemon running in domU and sending 
data to dom0 over IP, Xen bridged networking) the system becomes 
unstable after several minutes of backup. Sometimes dom0 crashes and 
reboots. Sometimes domUs IP network stops working.
If I don''t perform domU backup the system is stable.
If I run a backup of another computer (Bacula file daemon running on a 
Windows box), Lenny computer remains stable. So I suppose issue is 
related to higher disk activity when Bacula file daemon is running in 
domU. Dom0 and DomUs share the same physical disk, a SATA soft raid5 
array. When I run a backup of a Windows computer data is sent to Bacula 
storage daemon in dom0 via IP ethernet network and Bacula storage daemon 
writes that data on tape.
I didn''t have time to investigate further, cause I needed the system 
working for production.
I solved this issue installing Xen 3.4 (back-ported from Debian Squeeze) 
and Suse Linux Enterprise 11 kernel 
(http://wiki.xensource.com/xenwiki/XenDom0Kernels) on dom0 only.
Be aware that on Suse kernel some Xen networking features are compiled 
as modules, so you need to load them before starting domUs.



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

Pasi Kärkkäinen

2010-Feb-16 11:57 UTC

head link

Re: [Xen-users] Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1

On Fri, Feb 12, 2010 at 11:06:59PM +0100, Andrea Janna
wrote:> -------- Original message --------
> From: Thaddeus Hogan <thaddeus@thogan.com>
> Date: 05/11/2009 17.01
>> I''m looking for a place to start with a problem I am having
where I think
>> high network load is crashing my Xen host. Any help you can offer is
>> greatly appreciated!
>>
>> I started having an issue with my dom0 crashing when under very high
>> network load. I discovered this when I ran a large backup (1.7 TB) on a
>> domU.
>>    
>
> I had a similar problem last month. I''m running a Debian Lenny
dom0 with
> 3 Lenny domUs. Kernel 2.6.26 and all software packages are Lenny 
> releases.
> I use Bacula for backups on a DAT 72 tape device. Dom0 is running Bacula  
> storage daemon, which manage the DAT device itself.
> If I run a domU backup (Bacula file daemon running in domU and sending  
> data to dom0 over IP, Xen bridged networking) the system becomes  
> unstable after several minutes of backup. Sometimes dom0 crashes and  
> reboots. Sometimes domUs IP network stops working.
> If I don''t perform domU backup the system is stable.
> If I run a backup of another computer (Bacula file daemon running on a  
> Windows box), Lenny computer remains stable. So I suppose issue is  
> related to higher disk activity when Bacula file daemon is running in  
> domU. Dom0 and DomUs share the same physical disk, a SATA soft raid5  
> array. When I run a backup of a Windows computer data is sent to Bacula  
> storage daemon in dom0 via IP ethernet network and Bacula storage daemon  
> writes that data on tape.
> I didn''t have time to investigate further, cause I needed the
system
> working for production.
Wondering if these would have helped:
http://wiki.xensource.com/xenwiki/XenBestPractices
> I solved this issue installing Xen 3.4 (back-ported from Debian Squeeze)  
> and Suse Linux Enterprise 11 kernel  
> (http://wiki.xensource.com/xenwiki/XenDom0Kernels) on dom0 only.
> Be aware that on Suse kernel some Xen networking features are compiled  
> as modules, so you need to load them before starting domUs.
>
Yeah, SLES11 Xen kernel should be much more stable than lenny''s.

-- Pasi


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

Xen users - Nov 2009 - Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1

[Xen-users] Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1

Re: [Xen-users] Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1

Re: [Xen-users] Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1

Re: [Xen-users] Dom0 Crash - High Network Load - Debian Lenny Xen 3.2-1