Bug 654642

Summary:	dhclient -6 overwrites /etc/resolv.conf set up by NetworkManager
Product:	Red Hat Enterprise Linux 6	Reporter:	Jiri Popelka <jpopelka>
Component:	dhcp	Assignee:	Jiri Popelka <jpopelka>
Status:	CLOSED WONTFIX	QA Contact:	Release Test Team <release-test-team-automation>
Severity:	medium	Docs Contact:
Priority:	low
Version:	6.1	CC:	atodorov, ovasik
Target Milestone:	rc
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:	551962	Environment:
Last Closed:	2011-06-06 10:37:02 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	551962
Bug Blocks:

Description Jiri Popelka 2010-11-18 14:01:20 UTC

+++ This bug was initially created as a clone of Bug #551962 +++

Description of problem:

dhclient -6 (DHCP client for DHCPv6) overwrites setting in /etc/resolv.conf made by NetworkManager.

Version-Release number of selected component (if applicable):
dhclient-4.1.0p1-13.fc12.i686
NetworkManager-0.7.996-7.git20091113.fc12.i686

How reproducible:
100% of time.

Steps to Reproduce:
1. Connect to a network with NetworkManager supporting IPv4 and IPv6.
2. Invoke /sbin/dhclient -6 to obtain IPv6 not obtained by NetworkManager.
3.
  
Actual results:
Observe that in /etc/resolv.conf, the original information supplied by NetworkManager has been replaced by dhclient IPv6 information.  In particular all IPv4 addresses in nameserver lines have been replaced by IPv6 addresses.

Expected results:
Both IPv4 and IPv6 addresses should be available in /etc/resolv.conf.

Additional info:
This configuration is brought about by the fact that NetworkManager does not support the full RA option set, and in particular the "AdvManagedFlag on" setting.

--- Additional comment from jpopelka on 2010-04-12 16:11:08 CEST ---

Maybe interesting thread:
https://lists.isc.org/pipermail/dhcp-users/2010-April/011142.html

--- Additional comment from udovdh on 2010-09-14 16:56:05 CEST ---

Currently I am hacking dhclient-script etc for ipv6 PD support etc, so I might take a look at this problem as well. See https://bugzilla.redhat.com/show_bug.cgi?id=626514 for the pd/radvd stuff.

--- Additional comment from udovdh on 2010-09-14 17:18:33 CEST ---

Question: assuming we have the dns info from the dhcp server, plus also the local stuff that goes in resolv.conf, how would I combine that? I mean, in what order, what way?

# start local part
search bla.local
domain bla.local
server 127.0.0.1
# end local
# start dhcp part
search isp.com
server x.y.z.a
# end dhcp part

?

Comment 2 Jiri Popelka 2011-06-06 10:37:02 UTC

The solution to this problems is to have a middleman which takes the
nameserver information from each program (dhclient-script, NetworkManager, initscripts etc.) and merges them together to form one resolv.conf.
The openresolv program addresses this.

The problem is however that to use openresolv we need to modify all the resolv.conf writing packages to use openresolv instead of directly writing to resolv.conf. And that's not the way we want to go in RHEL-6.

Closing this as WONTFIX, because this change needs to be done in Fedora (bug #668153, bug #679445 and others). Moreover there's actually no customer behind this.