extraneous nameserver entries in resolv.conf

This continues a thread started in the applications forum:

mc hangs temporarily when network is down

mc (Midnight Commander) hangs on my desktop but not on my laptop. When I compared desktop and laptop configurations, I found the following differences:

/etc/hosts files:


Laptop:   127.0.0.2  linux-4xt8.site, linux-4xt8
Desktop:  127.0.0.2  linux-vnpi.site, linux-vnpi

/etc/host.conf files: No differences.

/etc/resolv.conf files: Laptop has nothing, desktop has the following four lines:


search cgocable.net
nameserver 24.226.1.93
nameserver 24.226.10.193
nameserver 24.226.10.194

/etc/sysconfig/network/config files:


Laptop:  NETWORKMANAGER="yes"
Desktop: NETWORKMANAGER="no"

I’d like to try changing the NETWORKMANAGER setting on the desktop to “yes” (after backing up /etc), but first I’d like to know where the extra nameserver records in resolv.conf came from. Could they be the reason why mc hangs?

I have one other problem symptom on the desktop: When I start xfce, I get the following message:

Could not look up internet address for x1-6-00-0c ...

On the laptop, it comes up clean.

Any advice?

The entries in /etc/resolv.conf most likely come from DHCP server and I think they are not the reason for mc hanging.
The entries might also come from the /etc/sysconfig/network/config file. There are two lines there :

#NETCONFIG_DNS_STATIC_SEARCHLIST=""
#NETCONFIG_DNS_STATIC_SERVERS=""

I’m really puzzled that your /etc/resolv.conf is empty on the laptop. What are You using to resolve DNS addresses on the Laptop ?

The error you get when starting xfce is this the whole message ?

Best regards,
Greg

On Fri March 4 2011 01:36 pm, glistwan wrote:

>
> The entries in /etc/resolv.conf most likely come from DHCP server and I
> think they are not the reason for mc hanging.
> The entries might also come from the /etc/sysconfig/network/config
> file. There are two lines there :
>
> Code:
> --------------------
> #NETCONFIG_DNS_STATIC_SEARCHLIST=“”
> #NETCONFIG_DNS_STATIC_SERVERS=“”
>
> --------------------
> I’m really puzzled that your /etc/resolv.conf is empty on the laptop.
> What are You using to resolve DNS addresses on the Laptop ?
>
> The error you get when starting xfce is this the whole message ?
>
> Best regards,
> Greg
>
>

NonZ;

The entries in /etc/resolv.conf are just the entries for your DNS. These
were either assigned statically via YaST or assigned by your dhcp server.
There is no reason to be concerned about these. Moreover, they should have no
effect on mc or xfce.

Unless you are in the habit of moving your desktop around and connecting to
different wireless networks; I would recommend that you do not change it to
Network Manager and leave it using ifup. If your heart is set on changing
this you can use YaST. See this Howto for instructions:

I don’t think either of your problems with mc or xfce are related to your
network settings, but rather to some process that is trying to use the
network and, of course, failing when you are disconnected. Maybe an E-mail
client that is set to automatically get messages. If you use mc to manipulate
remote directories (nfs, samba or “file over shell”(fish)) it maybe looking
for those directories.

P. V.
“We’re all in this together, I’m pulling for you.” Red Green

Thanks for the advice and the link to the helpful article.

I am still hoping that this desktop-only problem can be solved. I compared YaST network settings on the laptop with those on the desktop, and I found the following differences:


: Global Overview:
  : laptop: User controlled with Network Manager
  : desktop: Traditional method with ifup
: Overview:
  : laptop has two entries:
    : AR2413 802.11 bg NIC                       DHCP
    : SiS900 PCI Fast Ethernet                   DHCP
  : desktop has two entries:
    : Atheros AR5001X+ Wireless Network Adapter  Not Configured
    : VT6102 [Rhine-II]                          DHCP
: Hostname/DNS
  : laptop has: 
    : hostname linux-4xt8
    : Write hostname to /etc/hosts
  : desktop has:
    : hostname linux-vnpi
    : Change hostname via DHCP
    : Write hostname to /etc/hosts

Samba:
  : Both: Workgroup or domain name: WORKGROUP
  : Both: Primary domain controller
  : Both: Start-Up manually

(I checked Samba as well, because others who have reported this error say that mc’s Samba interface may be at fault – though that wouldn’t explain why xfce complains. The xfce message begins:

Could not look up internet address for x1-6-00-0c ...

The address in question is the MAC address for my eth0 NIC. Is xfce treating this as a 6-byte internet address?

Wanted to edit the above to shorten it and answer other questions, but I missed the 10-minute time-limit. Here’s the shorter message I wanted to post.


What are You using to resolve DNS addresses on the Laptop ?

The error you get when starting xfce is this the whole message ?

Configure a network card in Suse/openSUSE 11.x for Internet Access & wifi.

If you use mc to manipulate remote directories (nfs, samba or “file over shell”(fish)) it maybe looking for those directories.


Thanks for the advice and the link to the helpful article.

I am still hoping that this desktop-only problem can be solved. I compared YaST network settings on the laptop with those on the desktop, and I found the following differences:


: Global Overview:
  : laptop: User controlled with Network Manager
  : desktop: Traditional method with ifup
: Overview:
  : laptop has two entries:
    : AR2413 802.11 bg NIC                       DHCP
    : SiS900 PCI Fast Ethernet                   DHCP
  : desktop has two entries:
    : Atheros AR5001X+ Wireless Network Adapter  Not Configured
    : VT6102 [Rhine-II]                          DHCP
: Hostname/DNS
  : laptop has: 
    : hostname linux-4xt8
    : Write hostname to /etc/hosts
  : desktop has:
    : hostname linux-vnpi
    : Change hostname via DHCP
    : Write hostname to /etc/hosts

Samba:
  : Both: Workgroup or domain name: WORKGROUP
  : Both: Primary domain controller
  : Both: Start-Up manually

(I don’t use mc for remote acess. Nonetheless, I checked Samba, because others who have reported this error say that mc’s Samba interface may be at fault – though that wouldn’t explain why xfce complains. The xfce message begins:

Could not look up internet address for x1-6-00-0c ...

The rest of the message advises me to add the address to /etc/hosts (as I recall). The address in question is the MAC address for my eth0 NIC. Is xfce treating this as a 6-byte internet address?

/etc/sysconfig/network/config shows:


NETCONFIG_DNS_STATIC_SEARCHLIST=""
NETCONFIG_DNS_STATIC_SERVERS=""

How can I find out what the laptop is using for DNS?

I think You might want to delete the settings in bold in order to not have the hostname changed by your DHCP server.

The computer is using those servers that are currently in /etc/resolv.conf file. So the way to do this is just print the contents of the file.
Another way to test is to use :

nslookup <some_domain_name>

or

dig <some_domain_name>

but I think dig is not installed by default. In the answer You should get the information about which server resolved your query for example :

C:\Users\glistwan>nslookup opensuse.org
Server:  dns.server.name
Address:  8.8.8.8

Non-authoritative answer:
Name:    opensuse.org
Address:  130.57.5.70

The example is from Windows but it should look very similar on openSUSE.

Best regards,
Greg

On Mon March 7 2011 12:36 am, NonZ wrote:

>
> venzkep;2298430 Wrote:
>> On Fri March 4 2011 01:36 pm, glistwan wrote:
>>
>> >
<snip>

>
> Samba:
> : Both: Workgroup or domain name: WORKGROUP
> : Both: Primary domain controller
> : Both: Start-Up manually
>
> --------------------
>
>
> (I checked Samba as well, because others who have reported this error
> say that mc’s Samba interface may be at fault – though that wouldn’t
> explain why xfce complains. The xfce message begins:
>
>
> Code:
> --------------------
> Could not look up internet address for x1-6-00-0c …
> --------------------
>
>
> The address in question is the MAC address for my eth0 NIC. Is xfce
> treating this as a 6-byte internet address?
>
NonZ;

You can only have ONE PDC on a Samba3 or NT3 Domain. You need to change the
smb.conf on one of the machines. Do you really need a Domain or would a
simple workgroup setup suffice. What is your reason for using a Domain
model?
Unless you have a compelling reason to use a domain model, I suggest you
follow this Howto:

http://opensuse.swerdna.org/suselanprimer.html

The following two parameters should be in at most one of the
machines /etc/samba/smb.conf.


local master = yes
os level = 33

As for xfce; please post the results of:


/sbin/ifconfig -a

Do this for both when the machine is connected to the LAN and when it is not.


P. V.
“We’re all in this together, I’m pulling for you.” Red Green

Thank you for your interest, venzkep.

The desktop and laptop are not networked (to each other). Both connect directly to the internet. Maybe that is why each has a PDC.

I compared /etc/samba files for both and found only one differences: The desktop has a DHCP.conf file. However, the file contains only comments (#-lines).

Neither has a “local” entry. Neither has a “os level” entry.

I did “man inconfig” and found no “-a” option. I did find an “-a” (all) option with netstat.

I ran netstat with the eth0 cable plugged in (netstat.bef.txt), then ran it again with the cable unplugged.

The second netstat also seemed to hang on the desktop, but did eventually complete. On the laptop, netstat runs instantly, even when the eth0 cable is unplugged.

So the problem is not specific to mc!

The netstat output is too voluminous to post here. So I ran “diff -u netstat.bef.txt netstat.aft.txt” instead. Here is the result (with certain numbers X’d out for security reasons):


--- netstat.bef.txt     2011-03-09 17:05:53.132003195 -0500
+++ netstat.aft.txt     2011-03-09 17:07:49.768002411 -0500
@@ -3,17 +3,20 @@
 tcp        0      0 *:sunrpc                *:*                     LISTEN      
 tcp        0      0 localhost:ipp           *:*                     LISTEN      
 tcp        0      0 localhost:smtp          *:*                     LISTEN      
-tcp        0      0 dXX-XXX-XXX-XX.ho:36111 webcs208p4.msg.ac4:mmcc ESTABLISHED 
+tcp        0    104 dXX-XXX-XXX-XX.ho:36111 webcs208p4.msg.ac4:mmcc ESTABLISHED 
 tcp        0      0 *:sunrpc                *:*                     LISTEN      
 tcp        0      0 localhost:ipp           *:*                     LISTEN      
 tcp        0      0 localhost:smtp          *:*                     LISTEN      
 udp        0      0 dXX-XXX-XXX-XX.ho:57684 *:*                                 
+udp        0    320 dXX-XXX-XXX-XX.ho:45406 24.226.1.93:domain      ESTABLISHED 
 udp        0      0 *:sift-uft              *:*                                 
 udp        0      0 *:mdns                  *:*                                 
 udp        0      0 XXX.XXX.XXX.XXX:ssdp    *:*                                 
 udp        0      0 *:sunrpc                *:*                                 
 udp        0      0 *:ipp                   *:*                                 
+udp        0      0 dXX-XXX-XXX-XX.ho:35071 XX.XXX.X.XX:domain      ESTABLISHED 
 udp        0      0 *:41737                 *:*                                 
+udp        0      0 dXX-XXX-XXX-XX.ho:49565 XX.XXX.X.XX:domain      ESTABLISHED 
 udp        0      0 *:sift-uft              *:*                                 
 udp        0      0 *:sunrpc                *:*                                 
 Active UNIX domain sockets (servers and established)
@@ -77,6 +80,8 @@
 unix  2       ACC ]     STREAM     LISTENING     15435  /tmp/.esd-1000/socket
 unix  2       ACC ]     STREAM     LISTENING     15509  /tmp/orbit-XXX/linc-dXX-0-19509XXXXXXXX
 unix  2       ACC ]     STREAM     LISTENING     6157   /var/run/dbus/system_bus_socket
+unix  3       ]         STREAM     CONNECTED     100177 /var/run/nscd/socket
+unix  3       ]         STREAM     CONNECTED     100176 
 unix  2       ]         DGRAM                    91873  
 unix  3       ]         STREAM     CONNECTED     38245  @/tmp/dbus-Ad4LfjijCa
 unix  3       ]         STREAM     CONNECTED     38244  

Thanks for leading me to netstat. Now I have another important clue.

On Wed March 9 2011 04:36 pm, NonZ wrote:

>
> Thank you for your interest, venzkep.
>
> The desktop and laptop are not networked (to each other). Both connect
> directly to the internet. Maybe that is why each has a PDC.
>
> I compared /etc/samba files for both and found only one differences:
> The desktop has a DHCP.conf file. However, the file contains only
> comments (#-lines).
>
> Neither has a “local” entry. Neither has a “os level” entry.
>
> I did “man inconfig” and found no “-a” option. I did find an “-a”
> (all) option with netstat.
>
<snip>
>
> --------------------
>
>
> Thanks for leading me to netstat. Now I have another important clue.
>
>
Nonz;
From man ifconfig

If no arguments are given, ifconfig displays the status of the currently
active interfaces. If a single interface argument is given, it displays the
status of the given interface only; if a single -a argument is given, it
displays the status of all interfaces, even those that are down. Other wise,
it configures an interface.


P. V.
“We’re all in this together, I’m pulling for you.” Red Green

Sorry – I missed that! Here is “ifconfig -a” before unplugging:


eth0      Link encap:Ethernet  HWaddr XX:XX:XX:XX:XX:XX  
          inet addr:XX.XXX.XXX.XX  Bcast:255.255.255.255  Mask:255.255.252.0
          UP BROADCAST RUNNING MULTICAST  MTU:576  Metric:1
          RX packets:15138 errors:0 dropped:0 overruns:0 frame:0
          TX packets:14369 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:6074952 (5.7 Mb)  TX bytes:2314309 (2.2 Mb)
          Interrupt:23 Base address:0x8e00 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:349 errors:0 dropped:0 overruns:0 frame:0
          TX packets:349 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:32124 (31.3 Kb)  TX bytes:32124 (31.3 Kb)

wlan0     Link encap:Ethernet  HWaddr XX:XX:XX:XX:XX:XX  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

wmaster0  Link encap:UNSPEC  HWaddr XX-XX-XX-XX-XX-XX-XX-00-00-00-00-00-00-00-00-00  
          [NO FLAGS]  MTU:0  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

And here is “ifconfig -a” after unplugging the eth0 cable:


eth0      Link encap:Ethernet  HWaddr XX:XX:XX:XX:XX:XX  
          inet addr:XX.XXX.XXX.XX  Bcast:255.255.255.255  Mask:255.255.252.0
          UP BROADCAST MULTICAST  MTU:576  Metric:1
          RX packets:15138 errors:0 dropped:0 overruns:0 frame:0
          TX packets:14369 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:6074952 (5.7 Mb)  TX bytes:2314309 (2.2 Mb)
          Interrupt:23 Base address:0x8e00 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:349 errors:0 dropped:0 overruns:0 frame:0
          TX packets:349 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:32124 (31.3 Kb)  TX bytes:32124 (31.3 Kb)

wlan0     Link encap:Ethernet  HWaddr XX:XX:XX:XX:XX:XX  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

wmaster0  Link encap:UNSPEC  HWaddr XX-XX-XX-XX-XX-XX-XX-00-00-00-00-00-00-00-00-00  
          [NO FLAGS]  MTU:0  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

On Wed March 9 2011 05:36 pm, NonZ wrote:

>
> Sorry – I missed that! Here is “ifconfig -a” before unplugging:
>
>
> Code:
> --------------------
>
> eth0 Link encap:Ethernet HWaddr XX:XX:XX:XX:XX:XX
> inet addr:XX.XXX.XXX.XX Bcast:255.255.255.255 Mask:255.255.252.0
> UP BROADCAST RUNNING MULTICAST MTU:576 Metric:1
> RX packets:15138 errors:0 dropped:0 overruns:0 frame:0
> TX packets:14369 errors:0 dropped:0 overruns:0 carrier:0
> collisions:0 txqueuelen:1000
> RX bytes:6074952 (5.7 Mb) TX bytes:2314309 (2.2 Mb)
> Interrupt:23 Base address:0x8e00
>
<snip>
NonZ;

I was hoping to see at least the first few digits of the HWaddr (MAC) and
inet6 addr (IPv6). Can you confirm that “x1-6-00-0c …” is the first few
digits of the MAC address and that IPv6 is disabled both in YaST and
in /boot/grub/menu.lst. Although the later was written for 11.2, AFAIK it
also applies to 11.3.

See:

http://forums.opensuse.org/english/get-technical-help-here/how-faq-forums/unreviewed-how-faq/412555-disable-ipv6.html

and

http://forums.opensuse.org/new-user-how-faq-read-only/unreviewed-how-faq/433057-howto-disable-ipv6-opensuse-11-2-a.html

P. V.
“We’re all in this together, I’m pulling for you.” Red Green