Bug 508965

Summary: Disabling DHCP also turns off DNS forwarding for a libvirt network
Product: [Community] Virtualization Tools Reporter: Charles Duffy <charles_duffy>
Component: libvirtAssignee: Daniel Veillard <veillard>
Status: CLOSED CURRENTRELEASE QA Contact:
Severity: medium Docs Contact:
Priority: low    
Version: unspecifiedCC: berrange, crobinso, xen-maint
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OS: Linux   
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Last Closed: 2009-08-14 15:09:45 UTC Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Charles Duffy 2009-06-30 17:07:31 UTC
Description of problem:

Disabling libvirt-controlled DHCP (/network/ip/dhcp) also prevents DNS forwarding from being available to the relevant libvirt-controlled network.

This could be resolved by running dnsmasq with the --no-dhcp-

Version-Release number of selected component (if applicable):

0.6.4

How reproducible:

Every time

Steps to Reproduce:
1. Create a libvirt network without /network/ip/dhcp defined.
2. Start a guest in that network.
3. Attempt to resolve names through DNS through the host's IP on that network (/network/ip/@address)
  
Actual results:

DNS service should be available via the IP defined in the network XML at /network/ip/@address, just as it is with DHCP running.

Expected results:

No DNS redirection is available.

Additional info:

dnsmasq has a --no-dhcp-interface= argument which can be used to implement this functionality.

Comment 1 Daniel Berrangé 2009-08-14 15:09:45 UTC
This was addressed in the 0.7.0 release in the following commit


author:	Daniel P. Berrange <berrange>
	 Thu, 30 Jul 2009 13:52:31 +0000 (14:52 +0100)
commit:	df3de82c06d42fed832c1955dafdee85879bd15a

Allow dnsmasq to provide DNS without DHCP

* src/network_driver.c: Always start dnsmasq to allow it to provide
  DNS, even if no DHCP ranges are enabled