[CentOS] NetworkManager frustration...

Fri May 11 10:38:06 UTC 2012
Nux! <nux at li.nux.ro>

On 11.05.2012 11:16, Timothy Madden wrote:
> On 05/11/2012 11:14 AM, Nux! wrote:
>> On 10.05.2012 11:55, Timothy Madden wrote:
>>> I would like to use dnsmasq to cache nameserver query results, and 
>>> I
>>> have set dhcp to prepend the name-server to the list of
>>> nameservers. dnsmasq would then automatically exclude the localhost
>>> as a
>>> name server and use all the others from the list provided by dhcp.
>>> But it was too nice to be true, because NetworkManager was there,
>>> ready
>>> to mess up anything I try to do, including the list of name servers
>>> that
>>> dhclient puts in /etc/resolv.conf.
>>> Is there really no way to convince that idiotic piece of software
>>> that
>>> it suffered too much brain damage in order for it to manage even a
>>> simple eth0 interface, and that dhclient can properly take care of
>>> the
>>> resolver configuration by itself ?
>>> Or do I have to turn it off entirely ?
>>> Is there a better way to have dhclient write the list of DNS 
>>> servers,
>>> that dnsmasq could then use ?
>>> Thank you,
>>> Timothy Madden
>>> _______________________________________________
>>> CentOS mailing list
>>> CentOS at centos.org
>>> http://lists.centos.org/mailman/listinfo/centos
>> I'm doind the same thing (running local cache) and NM works just 
>> fine.
>> You should be setting NM to use the "DHCP (addresses only)" as in 
>> this
>> image: http://img.nux.ro/4PsJ-dhcpnmlocaldns.png
>> Put the upstream resolvers in some other file, e.g. /etc/nameservers
>> and tell dnsmasq to get it's nameservers from there.
>> Or just run a full fledge nameserver yourself and get rid of dnsmasq 
>> (I
>> use pdns-recursor).
> But if I make a separate file like /etc/nameservers than I will have 
> to
> update it every time DHCP returns a different list of nameservers.
> I tried to write a dhclient-exit-hooks script in /etc/dhcp that would
> generate that file, but guess what ? Network Manager supresses the
> normal dhclient script file ! (probably uses its own) I tried to add 
> it
> back with
>           DHCLIENTARGS="-sf /sbin/dhclient-script"
> with no effect, because NetworkManager takes care that such an 
> approach
> would not work !
> And if I try to read some documentation about how NetworkManager 
> would
> achieve the same effect, there is nothing clear in its manual pages, 
> you
> can only find some (vague) settings about NM plugins.
> How can such software be part of CentOS _base_ distribution ?

Well.. in many cases NM works well, hence it's presence in @base. Now I 
don't know how to solve your problem nor do I have time to investigate; 
all I can recommend is run a local dns cache (pdns-recursor, bind, 
tinydns etc).

Sent from the Delta quadrant using Borg technology!