[CentOS-virt] VMs failing to restart

[George Dunlap]

On Wed, Mar 26, 2014 at 11:20 AM, Lars Hecking
<lhecking at users.sourceforge.net> wrote:
>
>  This is a problem I've had on and off under CentOS5 and CentOS6, with both
>  xen and kvm. Currently, it happens consistently with kvm on 6.5, e.g. with
>  every kernel update. I *think* it generally worked fine with the 6.4 kernels.
>
>  There are 7 VMs running on a 6.5, x86_64, 8GB RAM host, each with 512MB RAM
>  and using the e1000 NIC. I picked this specific NIC because the default does
>  not allow reliable monitoring through SNMP (IIRC). The host has two bonded
>  NICs with br0 running on top.
>
>  When the host reboots, the VMs will generally hang bringing up the virtual
>  NIC, and I need to go through several iterations of destroy/create, for each
>  VM, to get them running. The always hang here (copy&paste from console):
>
> ...
>                 Welcome to CentOS
> Starting udev: udev: starting version 147
> piix4_smbus 0000:00:01.3: SMBus Host Controller at 0xb100, revision 0
> e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k8-NAPI
> e1000: Copyright (c) 1999-2006 Intel Corporation.
> ACPI: PCI Interrupt Link [LNKC] enabled at IRQ 11
> e1000 0000:00:03.0: PCI INT A -> Link[LNKC] -> GSI 11 (level, high) -> IRQ 11
> e1000 0000:00:03.0: eth0: (PCI:33MHz:32-bit) 00:16:3e:52:e3:0b
> e1000 0000:00:03.0: eth0: Intel(R) PRO/1000 Network Connection
>
>  Any suggestions on where to start looking?

Have you tried other virtual network cards, and/or PV network (netback
for Xen or virtio for KVM)?

That would help you isolate whether the problem was in the e1000
emulation (which I suspect is shared between KVM and Xen) or in the
host network configuration (which, it sounds like, is non-trivial).

 -George