/etc/resolv.conf getting over written with dhcp

[Dima Panov]

15.06.2012 23:09, Varuna написал:
> Hello Folks,
>
> Noticed a strange issue with the creation / update of 
> /etc/resolv.conf.  The details of the system that I noticed the issue 
> on is:
>   Version : FreeBSD 8.0
>   Patch level: not patched
>   Uname: FreeBSD shastry.eudaemonicsystems.net 8.0-RELEASE FreeBSD 
> 8.0-RELEASE #0: Thu Sep 29 22:37:51 IST 2011 
> root at shastry.bhuta.in:/usr/obj/usr/src/sys/SHASTRY  i386
>
>
> I generally have a static IP 192.168.98.6 (via rc.conf) for my 
> Beastie.  The contents of my /etc/resolv.conf is as follows:
>    domain eudaemonicsystems.net
>    nameserver 208.67.222.222
>    nameserver 208.67.220.220
>    nameserver 4.2.2.2
> No matter how many times I reboot the system, the resolv.conf does not 
> get overwritten when configured with a static IP.
>
> I modified the /etc/rc.conf to have the flag:
>    ifconfig_re0="DHCP"
> The next reboot of the system caused the /etc/resolv.conf to be 
> overwritten with the following contents:
>    nameserver 192.168.98.4
>
> I was baffled with this behaviour and checked /etc/rc.d/resolv script 
> and there was no reason as to why "[ ! -e /etc/resolv.conf]" should 
> fail at any given instance.  Out of curiosity executed "/bin/kenv 
> dhcp.domain-name" which returned with the info: kenv: unable to get 
> dhcp.domain-name.  Would it be fair to assume that /etc/rc.d/resolv 
> not to cause the issue?
>
> What is causing this behaviour? Have I missed something?
>
> Had a look at network-dhcp.html, and found /etc/dhclient.conf to be 
> empty on my system.
>
> Digging further, was looking at the scripts under /etc/rc.d, found 
> /etc/rc.d/named to be another script creating the /etc/resolv.conf and 
> this was in the routine named_precmd().  I have not enabled 
> 'named_enable' flag in /etc/rc.conf, while it is commented; by 
> default; in /etc/defaults/rc.conf file.
>

 From my /etc/dhclient.conf:

interface "lagg0" {
     send dhcp-lease-time 3600;
     prepend domain-name-servers 127.0.0.1, 4.4.4.4, 8.8.8.8;
     request subnet-mask, broadcast-address, time-offset, routers,
             domain-name, domain-name-servers;
     require subnet-mask, domain-name-servers;
}

And result is /etc/resolv.conf:
# Generated by resolvconf
nameserver 127.0.0.1
nameserver 4.4.4.4
nameserver 8.8.8.8
nameserver 192.168.1.1



-- 
Dima Panov (fluffy at FreeBSD.org)
(KDE, Office)@FreeBSD team

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