12.04 - libvirt - DNS not being resolved in guest by

**cmallwitz** · November 5th, 2012

I used to have a Windows 7 KVM/QEMU VM running under Ubuntu 10.04 and can't get it to run under 12.04.

As host I use a vanilla notebook installation of 12.04 using a wireless connection (so I can use NAT but not bridged networks in KVM/QEMU). The host notebook is part of a home network with a few more Windos machines and has the packages winbind and samba installed. Additionally, /etc/nsswitch.conf has 'hosts: files wins dns' to have all machines know/see each other without having to run a DNS server and/or use static IP addresses. I haven't noticed any other issues with the host from a networking perspective.

For KVM/QEMU the host has:

sudo apt-get -y install qemu-kvm libvirt-bin
sudo apt-get -y install virt-manager
sudo adduser $USER libvirtd
sudo adduser $USER kvm

My DHCP-enabled guest starts up fine and has IP connectivity to the outside world: I can ping 8.8.8.8 without problems but can't resolve DNS names using the default DNSMASQ process started by libvirt. If I manually change the guest's DNS server from the default 192.168.122.1 to 8.8.8.8 DNS names are resolved as expected.

On the host when running 'ps -ealf | grep dnsmasq' I can see two dnsmasq processes - I have not installed a dedicated dnsmasq service (so only package dnsmasq-base installed - not dnsmasq):

First the dnsmasq processes started by Network Manager:
/usr/sbin/dnsmasq --no-resolv --keep-in-foreground --no-hosts --bind-interfaces --pid-file=/var/run/sendsigs.omit.d/network-manager.dnsmasq.pid --listen-address=127.0.0.1 --conf-file=/var/run/nm-dns-dnsmasq.conf --cache-size=0 --proxy-dnssec

Second the dnsmasq process started by libvirt:
/usr/sbin/dnsmasq -u libvirt-dnsmasq --strict-order --bind-interfaces --pid-file=/var/run/libvirt/network/default.pid --conf-file= --except-interface lo --listen-address 192.168.122.1 --dhcp-range 192.168.122.2,192.168.122.254 --dhcp-leasefile=/var/lib/libvirt/dnsmasq/default.leases --dhcp-lease-max=253 --dhcp-no-override

I suspect the libvirt/dnsmasq process isn't configures correctly but I can't figure out how to fix it...

Any ideas?

Thanks
Christian

**cmallwitz** · November 20th, 2012

Would anybody think that running a laptop with WiFi/DHCP networking and a KVM/QEMU guest with NATed DHCP is an unusual set-up? If somebody else has the same set-up, how did you get it up and running? Did you get DNS working through libvirt's dnsmasq process? Do you have a full dnsmasq installed/setup? How?

Thanks
Christian