Host crash during backups

[rwadi]

(I posted this in the wrong section before, sorry for second post)

I have an issue with one of our ProxmoxVE hosts where it will randomly kernel panic during the nightly backups to an NFS server. I have no idea what is causing the problem.......

Here is the information I can give you:

1) I have two identical hosts (running standalone), one host is fine, the other randomly kernel panic during backups - usually about 10 minutes in. It seems stable apart from that.
2) Does not happen every time, seems to be once or twice a months (sometimes more often)
3) Host is running ProxmoxVE 2.3 (see pveversion output below)
4) Host is running Linux software raid1 for /boot and raid5 for pve lvm
5) I have had host backing up to a Debian NFS server, and to Synology RackStation, same results.
6) Host is running and backing up OpenVZ containers and KVM virtual machines
7) I don't see any useful information in any of the logs after the machine automatically reboots

As mentioned this issue seems to only happen on one of these identical hosts, and it does not happen on any of our other 7 hosts which are all running ProxmoxVE.

Any ideas what could be causing this? Let me know if there is any additional information that would be helpful.

root@host1:~# pveversion --verbose
pve-manager: 2.3-13 (pve-manager/2.3/7946f1f1)
running kernel: 2.6.32-19-pve
proxmox-ve-2.6.32: 2.3-96
pve-kernel-2.6.32-16-pve: 2.6.32-82
pve-kernel-2.6.32-19-pve: 2.6.32-96
pve-kernel-2.6.32-17-pve: 2.6.32-83
lvm2: 2.02.95-1pve2
clvm: 2.02.95-1pve2
corosync-pve: 1.4.4-4
openais-pve: 1.1.4-2
libqb: 0.10.1-2
redhat-cluster-pve: 3.1.93-2
resource-agents-pve: 3.9.2-3
fence-agents-pve: 3.1.9-1
pve-cluster: 1.0-36
qemu-server: 2.3-20
pve-firmware: 1.0-21
libpve-common-perl: 1.0-49
libpve-access-control: 1.0-26
libpve-storage-perl: 2.3-7
vncterm: 1.0-4
vzctl: 4.0-1pve2
vzprocps: 2.0.11-2
vzquota: 3.1-1
pve-qemu-kvm: 1.4-10
ksm-control-daemon: 1.1-1