does not update /etc/resolv.conf (when changed from NetworkManager)

[claes]

NetworkManager does not update /etc/resolv.conf. From the nm-applet, I can see the new retrieved IP address and DNS server addresses. But /etc/resolv.conf remains unchanged.

Claes

[Jonah Bull (jonahbull)]

AFAIK this is not a bug, but the result of a recent Ubuntu patch to network-manager. From the dapper-changes list:

  * 50-disable-named-and-vpn-managers.patch:
     - Remove the dependency on bind9 and all attempts to tinker with
       /etc/resolv.conf. Ubuntu's libc contains resolver patches to ensure
       changes are noticed by running applications; also our dhclient
       configuration handles writing resolv.conf itself and we're not yet
       allowing NetworkManager to manage static interfaces and VPN
       connections.

[Scott James Remnant (Canonical) (canonical-scott)]

Network Manager makes no attempt to update /etc/resolv.conf -- it leaves that up to dhclient3.

Please confirm that you DO NOT have the unsupported "resolvconf" package installed.

Attach your /etc/dhcp3/dhclient-script

Also attach listing of the /etc/dhcp3/dhclient-enter-hooks.d directory.

[Jie Zhang (jzhang918)]

This is the /etc/dhcp3/dhclient-script in my notebook.

[Jie Zhang (jzhang918)]

I don't have resolvconf package installed.

My /etc/dhcp3/dhclient-script has been added as an attachment.

There are two files in /etc/dhcp3/dhclient-enter-hooks.d directory:

/etc/dhcp3/dhclient-enter-hooks.d$ cat debug
# $Id: debug-enter,v 1.2 2003/06/18 18:11:21 peloy Exp $
#
# The purpose of this script is just to show the variables that are
# available to all the scripts in this directory. All these scripts
# are called from /etc/dhcp3/dhclient-script, which exports all the
# variables shown before. If you want to debug a problem with your DHCP
# setup you can enable this script and take a look at
# /tmp/dhclient-script.debug.

# To enable this script set the following variable to "yes"
RUN="no"

if [ "$RUN" = "yes" ]; then
        echo `date`: entering dhclient-enter-hooks.d, dumping variables. \
                >> /tmp/dhclient-script.debug

        for i in reason interface medium alias_ip_address new_ip_address \
                new_subnet_mask new_domain_name new_domain_name_servers \
                new_routers new_static_routes old_ip_address old_subnet_mask \
                old_domain_name old_domain_name_servers old_routers \
                old_static_routes; do

                echo $i=\'${!i}\' >> /tmp/dhclient-script.debug
        done

        echo '--------------------------' >> /tmp/dhclient-script.debug
fi

/etc/dhcp3/dhclient-enter-hooks.d$ cat samba
#!/bin/sh

SAMBA_DHCP_CONF=/etc/samba/dhcp.conf

netbios_setup() {
        # No need to continue if we're called with an unsupported option

        if [ "$reason" != BOUND ] && [ "$reason" != RENEW ] \
           && [ "$reason" != REBIND ] && [ "$reason" != REBOOT ] \
           && [ "$reason" != EXPIRE ] && [ "$reason" != FAIL ]
        then
                return
        fi

        # Nor should we continue if no settings have changed
        if [ "$new_netbios_name_servers" = "$old_netbios_name_servers" ] \
           && [ "$new_netbios_scope" = "$old_netbios_scope" ]
        then
                return
        fi

        # reparse our own file
        local other_servers=`sed -n -e"s/[[:space:]]$interface:[^[:space:]]*//g; \
                s/^[[:space:]]*wins server[[:space:]]*=[[:space:]]*//pi" \
                $SAMBA_DHCP_CONF`

        umask 022

        local serverlist="$other_servers"
        for server in $new_netbios_name_servers
        do
                serverlist="$serverlist $interface:$server"
        done

        echo -n > $SAMBA_DHCP_CONF

        # If we're updating on failure/expire, AND there are no WINS
        # servers for other interfaces, leave the file empty.
        if [ -z "$other_servers" ]
        then
                if [ "$reason" = FAIL ] || [ "$reason" = EXPIRE ]
                then
                        return
                fi
        fi

        if [ -n "$serverlist" ]
        then
                echo " wins server =$serverlist" >> $SAMBA_DHCP_CONF
        fi
        if [ -n "$new_netbios_scope" ]
        then
                echo " netbios scope = $new_netbios_scope" >> $SAMBA_DHCP_CONF fi
}

netbios_setup

[Jie Zhang (jzhang918)]

Forgot to mention, my network-manager and nm-applet both are 0.5.1-0ubuntu14. dhcp3-client is 3.0.3-6ubuntu4.

[Jie Zhang (jzhang918)]

Some more information. These are the last several lines from /var/log/daemon.log:

Feb 20 21:08:32 localhost NetworkManager: <information>^IOld device 'eth0' activating, won't change.
Feb 20 21:08:33 localhost NetworkManager: <information>^IActivation (eth0) Beginning DHCP transaction.
Feb 20 21:08:33 localhost NetworkManager: <information>^IActivation (eth0) Stage 3 (IP Configure Start) complete.
Feb 20 21:08:33 localhost NetworkManager: <information>^IDHCP daemon state now 12 for interface eth0
Feb 20 21:08:34 localhost NetworkManager: <information>^IDHCP daemon state now 1 for interface eth0
Feb 20 21:08:36 localhost dhclient: DHCPREQUEST on eth0 to 255.255.255.255 port 67
Feb 20 21:08:36 localhost dhclient: DHCPACK from 192.168.0.1
Feb 20 21:08:36 localhost dhclient: bound to 192.168.0.124 -- renewal in 235929 seconds.
Feb 20 21:08:36 localhost NetworkManager: <information>^IDHCP daemon state now 4 for interface eth0
Feb 20 21:08:36 localhost NetworkManager: <information>^IActivation (eth0) Stage 4 (IP Configure Get) scheduled...
Feb 20 21:08:36 localhost NetworkManager: <information>^IActivation (eth0) Stage 4 (IP Configure Get) started...
Feb 20 21:08:36 localhost NetworkManager: <WARNING>^I (): get_ip4_string(): error calling 'domain_name', DHCP daemon returned error 'org.freedesktop.DBus.Error.UnknownMethod', message 'Method "domain_name" with signature "" on interface "com.redhat.dhcp.dbus.get" doesn't exist '.
Feb 20 21:08:36 localhost NetworkManager: <information>^IRetrieved the following IP4 configuration from the DHCP daemon:
Feb 20 21:08:36 localhost NetworkManager: <information>^I address 192.168.0.124
Feb 20 21:08:36 localhost NetworkManager: <information>^I netmask 255.255.255.0
Feb 20 21:08:36 localhost NetworkManager: <information>^I broadcast 192.168.0.255
Feb 20 21:08:36 localhost NetworkManager: <information>^I gateway 192.168.0.1
Feb 20 21:08:36 localhost NetworkManager: <information>^I nameserver 202.96.209.5
Feb 20 21:08:36 localhost NetworkManager: <information>^I nameserver 202.96.209.133
Feb 20 21:08:36 localhost NetworkManager: <information>^IActivation (eth0) Stage 5 (IP Configure Commit) scheduled...
Feb 20 21:08:36 localhost NetworkManager: <information>^IActivation (eth0) Stage 4 (IP Configure Get) complete.
Feb 20 21:08:36 localhost NetworkManager: <information>^IActivation (eth0) Stage 5 (IP Configure Commit) started...
Feb 20 21:08:36 localhost NetworkManager: <information>^IYour IP address = 192.168.0.124
Feb 20 21:08:37 localhost NetworkManager: <information>^IActivation (eth0) Finish handler scheduled.
Feb 20 21:08:37 localhost NetworkManager: <information>^IActivation (eth0) Stage 5 (IP Configure Commit) complete.
Feb 20 21:08:37 localhost NetworkManager: <information>^IActivation (eth0) successful, device activated.

[Scott James Remnant (Canonical) (canonical-scott)]

And what does your /etc/resolv.conf look like at this point?

[Jie Zhang (jzhang918)]

I have no old /etc/resolv.conf at hand, since I run "/etc/init.d/networking restart" to report it. But I remember it contained two or three old DNS server addresses, which was for another LAN. I removed /etc/resolv.conf and rebooted my notebook, /etc/resolv.conf was not created.

[Scott James Remnant (Canonical) (canonical-scott)]

Maritn, any idea why /etc/resolv.conf isn't getting written here?

[fangorious (fangorious-deactivatedaccount)]

I'm having this same problem, with dhcp3-client 3.0.3-6ubuntu4. I'm attaching the files requested above.

[fangorious (fangorious-deactivatedaccount)]

listing of hooks.d folder

[fangorious (fangorious-deactivatedaccount)]

my dhclient.conf file.

[fangorious (fangorious-deactivatedaccount)]

Fortunately I can right-click on nm-applet to get Connection Information and write a working resolv.conf by hand.

[Scott James Remnant (Canonical) (canonical-scott)]

It seems that pitti spent a while making sure dhclient did nothing for dhcdbd-controlled interfaces ... will get him to remove this stuff and it should work.

[Martin Pitt (pitti)]

Well, this dhcdbd patch is ancient, and dates back to the early days of n-m, when Thom made dhcp3 work with that n-m.

I'll remove the patch.

[Martin Pitt (pitti)]

 dhcp3 (3.0.3-6ubuntu5) dapper; urgency=low
 .
   * Remove dhclient-dhcdbd-support.dpatch, remove dhcdbd stuff from
     debian/dhclient-script.linux. Nowadays network-manager relies on dhclient
     to rewrite resolv.conf. (Malone #32134)

[bhaagensen (bhaagensen)]

Hm, are you sure the dhcdb patch was safe to remove. I'm getting an error now which from the n-m list seems to be related to the patch? I've attached output form /var/log/syslog and /var/log/messages

_____________

syslog

Feb 20 22:39:24 localhost dhcdbd: message_handler: message handler not found under /com/redhat/dhcp/eth0 for sub-path eth0.dbus.get.reason
Feb 20 22:39:24 localhost NetworkManager: <information>^IWill activate wired connection 'eth0' because it now has a link.
Feb 20 22:39:24 localhost NetworkManager: <information>^IDevice eth0 activation scheduled...
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) started...
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) Stage 1 (Device Prepare) scheduled...
Feb 20 22:39:24 localhost NetworkManager: <information>^IOld device 'eth0' activating, won't change.
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) Stage 1 (Device Prepare) started...
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) Stage 2 (Device Configure) scheduled...
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) Stage 1 (Device Prepare) complete.
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) Stage 2 (Device Configure) starting...
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0/wired) Stage 2 (Device Configure) successful.
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) Stage 3 (IP Configure Start) scheduled.
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) Stage 2 (Device Configure) complete.
Feb 20 22:39:24 localhost NetworkManager: <information>^IActivation (eth0) Stage 3 (IP Configure Start) started...
Feb 20 22:39:24 localhost kernel: [4296008.727000] eth0: link up, 100Mbps, full-duplex, lpa 0x45E1
Feb 20 22:39:24 localhost kernel: [4296008.727000] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
Feb 20 22:39:25 localhost NetworkManager: <information>^IActivation (eth0) Beginning DHCP transaction.
Feb 20 22:39:25 localhost NetworkManager: <information>^IActivation (eth0) Stage 3 (IP Configure Start) complete.
Feb 20 22:39:25 localhost dhclient: Internet Systems Consortium DHCP Client V3.0.3
Feb 20 22:39:25 localhost dhclient: Copyright 2004-2005 Internet Systems Consortium.
Feb 20 22:39:25 localhost dhclient: All rights reserved.
Feb 20 22:39:25 localhost dhclient: For info, please visit http://www.isc.org/products/DHCP
Feb 20 22:39:25 localhost dhclient: Usage: dhclient [-1dqr] [-nw] [-p <port>] [-s server]
Feb 20 22:39:25 localhost dhclient: [-cf config-file] [-lf lease-file][-pf pid-file] [-e VAR=val]
Feb 20 22:39:25 localhost dhclient: [-sf script-file] [interface]
Feb 20 22:39:25 localhost dhcdbd: Unrequested down ?:3
Feb 20 22:39:25 localhost NetworkManager: <information>^IDHCP daemon state now 12 for interface eth0
Feb 20 22:39:25 localhost NetworkManager: <information>^IDHCP daemon state now 14 for interface eth0
Feb 20 22:39:34 localhost kernel: [4296019.082000] eth0: no IPv6 routers present

---------------------------

messages

Feb 20 22:39...

[bhaagensen (bhaagensen)]

I should perhaps add that I'm running the latest n-m, i.e. dhcp3 (3.0.3-6ubuntu5) and all other updated packages. I've made no changes to the default configuraiton in /etc/dhcp3

[Jie Zhang (jzhang918)]

I upgraded to the lastest versions. I have the same issue as bhaagensen and find same things in daemon.log.

[Martin Pitt (pitti)]

See bug #32223, fixing now.

[fangorious (fangorious-deactivatedaccount)]

Today's update to dhcdbd and dhcp3 fixed this problem for me

[Jie Zhang (jzhang918)]

It works for me now, too. Thanks!

[guidol (monk-e)]

Someone forgot to close the network-manager part of this bug.
Closing.