compute-002:~# uname -a
Linux compute-002 3.2.0-27-generic #43-Ubuntu SMP Fri Jul 6 14:25:57 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
compute-002:~# dpkg -l|egrep "kvm|libvirt|dhcp|dns"
ii dnsmasq-base 2.59-4 Small caching DNS proxy and DHCP/TFTP server
ii dnsmasq-utils 2.59-4 Utilities for manipulating DHCP leases
ii dnsutils 1:9.8.1.dfsg.P1-4ubuntu0.1 Clients provided with BIND
ii isc-dhcp-client 4.1.ESV-R4-0ubuntu5.1 ISC DHCP client
ii isc-dhcp-common 4.1.ESV-R4-0ubuntu5.1 common files used by all the isc-dhcp* packages
ii kvm-ipxe 1.0.0+git-3.55f6c88-0ubuntu1 PXE ROM's for KVM
ii libdns81 1:9.8.1.dfsg.P1-4ubuntu0.1 DNS Shared Library used by BIND
ii libnet-dns-perl 0.66-2ubuntu3 Perform DNS queries from a Perl script
ii libvirt-bin 0.9.8-2ubuntu17.2 programs for the libvirt library
ii libvirt0 0.9.8-2ubuntu17.2 library for interfacing with different virtualization systems
ii munin-libvirt-plugins 0.0.6-1 Munin plugins using libvirt
ii nova-compute-kvm 2012.1+stable~20120612-3ee026e-0ubuntu1.2 OpenStack Compute - compute node (KVM)
ii python-libvirt 0.9.8-2ubuntu17.2 libvirt Python bindings
ii qemu-kvm 1.0+noroms-0ubuntu14 Full virtualization on i386 and amd64 hardware
We've also tested this with kernel 3.5 backport from Quantal:
Linux compute-002 3.5.0-6-generic #6~precise1-Ubuntu SMP Tue Jul 24 14:45:23 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
The guest is running Debian Squeeze:
debian-squeeze-amd64-ext3:~$ uname -a
Linux debian-squeeze-amd64-ext3 2.6.32-5-amd64 #1 SMP Mon Jan 16 16:22:28 UTC 2012 x86_64 GNU/Linux
debian-squeeze-amd64-ext3:~$ dpkg -l|grep dhcp
ii isc-dhcp-client 4.1.1-P1-15+squeeze3 ISC DHCP client
ii isc-dhcp-common 4.1.1-P1-15+squeeze3 common files used by all the isc-dhcp* packages
We've found that having vhost_net module and using bridged networking breaks DHCP and guest do not get an IP address.
The issue has been properly described in the following RH doc:
http:// docs.redhat. com/docs/ en-US/Red_ Hat_Enterprise_ Linux/6/ html/Virtualiza tion_Host_ Configuration_ and_Guest_ Installation_ Guide/ch11s02. html
"11.2.1. Checksum correction for older DHCP clients"
Their workaround works in Precise too in fact.
Another workaround is to disable/unload the vhost_net module so new guests do make use of it.
RH has fixed this stuff in libvirt apparently:
"This iptables rule is programmed automatically on the host when the server is started by libvirt, so no further action is required"
My apologies if this stuff does not belong to libvirt.
Some info from our environment:
compute-002:~# lsb_release -rd
Description: Ubuntu 12.04 LTS
Release: 12.04
compute-002:~# uname -a
Linux compute-002 3.2.0-27-generic #43-Ubuntu SMP Fri Jul 6 14:25:57 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
compute-002:~# dpkg -l|egrep "kvm|libvirt| dhcp|dns" dfsg.P1- 4ubuntu0. 1 Clients provided with BIND R4-0ubuntu5. 1 ISC DHCP client R4-0ubuntu5. 1 common files used by all the isc-dhcp* packages 3.55f6c88- 0ubuntu1 PXE ROM's for KVM dfsg.P1- 4ubuntu0. 1 DNS Shared Library used by BIND plugins 0.0.6-1 Munin plugins using libvirt stable~ 20120612- 3ee026e- 0ubuntu1. 2 OpenStack Compute - compute node (KVM) 0ubuntu14 Full virtualization on i386 and amd64 hardware
ii dnsmasq-base 2.59-4 Small caching DNS proxy and DHCP/TFTP server
ii dnsmasq-utils 2.59-4 Utilities for manipulating DHCP leases
ii dnsutils 1:9.8.1.
ii isc-dhcp-client 4.1.ESV-
ii isc-dhcp-common 4.1.ESV-
ii kvm-ipxe 1.0.0+git-
ii libdns81 1:9.8.1.
ii libnet-dns-perl 0.66-2ubuntu3 Perform DNS queries from a Perl script
ii libvirt-bin 0.9.8-2ubuntu17.2 programs for the libvirt library
ii libvirt0 0.9.8-2ubuntu17.2 library for interfacing with different virtualization systems
ii munin-libvirt-
ii nova-compute-kvm 2012.1+
ii python-libvirt 0.9.8-2ubuntu17.2 libvirt Python bindings
ii qemu-kvm 1.0+noroms-
We've also tested this with kernel 3.5 backport from Quantal:
Linux compute-002 3.5.0-6-generic #6~precise1-Ubuntu SMP Tue Jul 24 14:45:23 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
The guest is running Debian Squeeze:
debian- squeeze- amd64-ext3: ~$ uname -a squeeze- amd64-ext3 2.6.32-5-amd64 #1 SMP Mon Jan 16 16:22:28 UTC 2012 x86_64 GNU/Linux
Linux debian-
debian- squeeze- amd64-ext3: ~$ dpkg -l|grep dhcp 15+squeeze3 ISC DHCP client 15+squeeze3 common files used by all the isc-dhcp* packages
ii isc-dhcp-client 4.1.1-P1-
ii isc-dhcp-common 4.1.1-P1-