OpenStack Compute (nova)

Windows VM unable to accept IP address from dnsmasq

Asked by Kenneth Jiang

When I launched a windows VM (image created by following http://docs.openstack.org/diablo/openstack-compute/admin/content/creating-a-windows-image.html), the Windows VM was unable to get an IP assigned:

Administrator> ipconfig /renew

Windows IP Configuration

An error occurred while renewing interface Local Area Connection : unable to contact your DHCP server. Request has timed out.

Openstack Dashboard shows that this instance is assigned IP 172.16.0.8, and I found the following in syslog:

Dec 8 05:59:54 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPDISCOVER(br100) 02:16:3e:11:59:7a
Dec 8 05:59:54 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPOFFER(br100) 172.16.0.8 02:16:3e:11:59:7a
Dec 8 05:59:57 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPDISCOVER(br100) 02:16:3e:11:59:7a
Dec 8 05:59:57 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPOFFER(br100) 172.16.0.8 02:16:3e:11:59:7a
Dec 8 06:00:05 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPDISCOVER(br100) 02:16:3e:11:59:7a
Dec 8 06:00:05 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPOFFER(br100) 172.16.0.8 02:16:3e:11:59:7a
Dec 8 06:00:20 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPDISCOVER(br100) 02:16:3e:11:59:7a
Dec 8 06:00:20 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPOFFER(br100) 172.16.0.8 02:16:3e:11:59:7a

Obviously the Windows VM was firing quite a few DHCP requests in 30 seconds, and dnsmasq responded each time with a DHCPOFFER, but somehow that IP address didn't get picked up by Windows VM.

I have a few Linux VMs (Ubuntu) running in the same nova installation and they are running fine. One observation, however, is that when Linux VMs sent DHCPDISCOVER, dnsmasq responded with DHCPACK, rather than DHCPOFFER. An example is:

Dec 8 06:00:10 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPREQUEST(br100) 172.16.0.6 02:16:3e:73:4d:54
Dec 8 06:00:10 cloud-ProLiant-DL160-G6 dnsmasq-dhcp[3140]: DHCPACK(br100) 172.16.0.6 02:16:3e:73:4d:54 test1

I'm wondering why dnsmasq gave "special treatment" to Windows VM, and if that was the cause of my problem.

Your help is really appreciated!

Question information

Language:
English Edit question
Status:
Solved
For:
OpenStack Compute (nova) Edit question
Assignee:
No assignee Edit question
Solved by:
Kenneth Jiang
Solved:
Last query:
Last reply:
Revision history for this message
Kenneth Jiang (kenneth-jiang) said : 		#1

Problem resolved by "killall dnsmasq; service nova-network restart". Now syslog spits out DHCPACK (as opposed to previous DHCPOFFER) for Windows VM, the same as it does for Linux.