Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 21 Aug 2012 11:57:56 +0900
From:      Hajimu UMEMOTO <ume@FreeBSD.ORG>
To:        Andrey Chernov <ache@FreeBSD.ORG>
Cc:        svn-src-head@FreeBSD.ORG, svn-src-all@FreeBSD.ORG, src-committers@FreeBSD.ORG, John Baldwin <jhb@FreeBSD.ORG>
Subject:   Re: svn commit: r239356 - head/sbin/dhclient
Message-ID:  <ygeharxdk97.wl%ume@mahoroba.org>
In-Reply-To: <20120821010311.GA8250@vniz.net>
References:  <201208171553.q7HFrhuf090457@svn.freebsd.org> <201208171507.07699.jhb@freebsd.org> <20120818195724.GA74684@vniz.net> <201208201409.55544.jhb@freebsd.org> <20120821010311.GA8250@vniz.net>

next in thread | previous in thread | raw e-mail | index | archive | help
Hi,

>>>>> On Tue, 21 Aug 2012 05:03:11 +0400
>>>>> Andrey Chernov <ache@FreeBSD.ORG> said:

ache> Having dual-stack machine it seems proper way for me to run both DHCP and 
ache> DHCPv6 clients (net-mgmt/wide-dhcp? net/dhcp6?). But I fear they both will 
ache> interact with single /etc/resolv.conf overriding each other there.

FreeBSD 9 and above already have a feature to handle multiple source
of DNS address,; resolvconf(8).  Our dhclient(8) and rtsol(8) uses it
to write /etc/resolv.conf.

ache> As I already mention, perhaps it is router bug combined with the lack of 
ache> validity checking in dhclient itself. As result I currently have
ache> /etc/resolv.conf:
ache> nameserver 192.168.1.1
ache> nameserver <ipv6 address of the tunnel NS>

Don't you see `# Generated by resolvconf' line in your generated
/etc/resolv.conf?
DHCP cannot carry an IPv6 address.
I suspect your router advertises an IPv6 address of your DNS server.
You can confirm where the DNS server addresss come from by executing
`resolvconf -l'.
The following is the output on my box for example:

ume@yuga:~% resolvconf -l
# resolv.conf from em0:dhcpv6
search mahoroba.org
nameserver 2001:2f0:104:8010::1
nameserver 2001:2f0:104:8010:221:5aff:feeb:183

# resolv.conf from em0:slaac:[fe80::218:71ff:feec:5271]
nameserver 2001:2f0:104:8010::1
search mahoroba.org

# resolv.conf from em0
search mahoroba.org
nameserver 192.168.100.59
nameserver 192.168.100.55 

My network announces DHCPv6 and my box is configured to use DHCPv6.
So, there are three sources for a DNS address, here.

Sincerely,

--
Hajimu UMEMOTO
ume@mahoroba.org  ume@{,jp.}FreeBSD.org
http://www.mahoroba.org/~ume/



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?ygeharxdk97.wl%ume>