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