[Samba] Nmbd is using the wrong ip address as source

Teodor Iacob theo at macsys.eu
Wed Oct 8 06:21:45 GMT 2008


Also nmblookup is using the external ip address:
 
querying HDV on 10.10.10.255
09:19:19.461813 IP X.X.X.X.45781 > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): QUERY; REQUEST; BROADCAST
09:19:19.732139 IP X.X.X.X.45781 > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): QUERY; REQUEST; BROADCAST
09:19:20.002136 IP X.X.X.X.45781 > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): QUERY; REQUEST; BROADCAST
name_query failed to find name HDV

The debugging information would show:
params.c:pm_process() - Processing configuration file "/etc/samba/smb.conf"
Processing section "[global]"
doing parameter workgroup = HOSTNAME
doing parameter netbios name = HDV
handle_netbios_name: set global_myname to: HDV
doing parameter interfaces = 10.10.10.1
doing parameter hosts allow = 127.0.0., 10.10.10.
doing parameter bind interfaces only = yes
doing parameter socket options = IPTOS_LOWDELAY TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
doing parameter preferred master = yes
doing parameter domain master = yes
doing parameter local master = yes
doing parameter os level = 100
doing parameter remote announce = 10.10.10.255/HOSTNAME
doing parameter socket address = 10.10.10.255
doing parameter log level = 1
..
added interface ip=10.10.10.1 bcast=10.10.10.255 nmask=255.255.255.0
socket option SO_KEEPALIVE = 0
socket option SO_REUSEADDR = 1
socket option SO_BROADCAST = 1
..
Socket opened.
querying HDV on 10.10.10.255
Sending a packet of len 50 to (10.10.10.255) on port 137
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
Sending a packet of len 50 to (10.10.10.255) on port 137
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
Sending a packet of len 50 to (10.10.10.255) on port 137
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
tdb(unnamed): tdb_open_ex: could not open file /var/cache/samba/unexpected.tdb: No such file or directory
name_query failed to find name HDV
..
 
 

  _____  

From: Frank Gruman [mailto:fgatwork at verizon.net] 
Sent: Tuesday, October 07, 2008 3:29 AM
To: Teodor Iacob
Cc: samba at lists.samba.org
Subject: RE: [Samba] Nmbd is using the wrong ip address as source


On Mon, 2008-10-06 at 09:05 +0300, Teodor Iacob wrote: 

Hello, 

Sorry for seeming impatient, I just had some rough night hours because of this problem :) 

tcpdump shows: 

08:21:22.920832 IP X.X.X.X.netbios-dgm > 10.10.10.255.netbios-dgm: NBT UDP PACKET(138)
08:21:22.920986 IP X.X.X.X.netbios-dgm > 10.10.10.255.netbios-dgm: NBT UDP PACKET(138)
08:21:23.072063 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): REGISTRATION; REQUEST; BROADCAST
08:21:23.072069 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): REGISTRATION; REQUEST; BROADCAST
08:21:23.072073 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): REGISTRATION; REQUEST; BROADCAST
08:21:23.072076 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): REGISTRATION; REQUEST; BROADCAST
08:21:23.072079 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): REGISTRATION; REQUEST; BROADCAST
08:21:24.072491 IP X.X.X.X.netbios-dgm > 10.10.10.255.netbios-dgm: NBT UDP PACKET(138)
08:21:24.072497 IP X.X.X.X.netbios-dgm > 10.10.10.255.netbios-dgm: NBT UDP PACKET(138)
08:21:24.072656 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): QUERY; REQUEST; BROADCAST
08:21:25.073432 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): REGISTRATION; REQUEST; BROADCAST
08:21:25.073438 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): REGISTRATION; REQUEST; BROADCAST
08:21:25.073441 IP X.X.X.X.netbios-ns > 10.10.10.255.netbios-ns: NBT UDP PACKET(137): REGISTRATION; REQUEST; BROADCAST



( where X.X.X.X is the public ip address of the linux server from eth0 ), this tcpdump was taken from another linux machine with the 

ip: 10.10.10.2 

The requested netstat output: 

[root at ns ~]# netstat -nap |grep [sn]mbd
tcp        0      0 10.10.10.1:139              0.0.0.0:*                   LISTEN      18538/smbd
tcp        0      0 10.10.10.1:445              0.0.0.0:*                   LISTEN      18538/smbd
udp        0      0 10.10.10.1:137              0.0.0.0:*                               18542/nmbd
udp        0      0 10.10.10.255:137            0.0.0.0:*                               18542/nmbd
udp        0      0 10.10.10.1:138              0.0.0.0:*                               18542/nmbd
udp        0      0 10.10.10.255:138            0.0.0.0:*                               18542/nmbd
unix  2      [ ]         DGRAM                    194986 18542/nmbd
unix  2      [ ]         DGRAM                    194960 18538/smbd



nmblookup from both machines returns this: 

querying server on 10.10.10.255
name_query failed to find name server 

Right now there are no PCs open in the network, but friday when I was testing various configurations, 

I was able to see that one of the XP machines reported back as master browser ( I could see the share list 

with _MSBROWSE_ as well. ) 


  

However if I do a unicast request to 10.10.10.1 ( basically it acts as a wins server ): 

querying HDV on 10.10.10.1
10.10.10.1 HDV<00>



In the nmbd.log I have: 

[2008/10/06 08:52:50, 0] nmbd/nmbd.c:main(698)
  Netbios nameserver version 3.0.28-1.el5_2.1 started.
  Copyright Andrew Tridgell and the Samba Team 1992-2007
[2008/10/06 08:52:51, 0] nmbd/nmbd_become_dmb.c:become_domain_master_browser_bcast(290)
  become_domain_master_browser_bcast:
  Attempting to become domain master browser on workgroup HOSTNAME on subnet 10.10.10.1
[2008/10/06 08:52:51, 0] nmbd/nmbd_become_dmb.c:become_domain_master_browser_bcast(303)
  become_domain_master_browser_bcast: querying subnet 10.10.10.1 for domain master browser on workgroup HOSTNAME
[2008/10/06 08:53:01, 0] nmbd/nmbd_become_dmb.c:become_domain_master_stage2(113)
  ***** 

  Samba server HNS is now a domain master browser for workgroup HOSTNAME on subnet 10.10.10.1 

  *****
[2008/10/06 08:53:15, 0] nmbd/nmbd_become_lmb.c:become_local_master_stage2(396)
  ***** 

  Samba name server HNS is now a local master browser for workgroup HOSTNAME on subnet 10.10.10.1 

  *****



Thank you for your time! 

Teodor 




  _____  


From: Frank Gruman [mailto:fgatwork at verizon.net] 
Sent: Sunday, October 05, 2008 10:28 PM
To: Teodor Iacob
Cc: samba at lists.samba.org
Subject: RE: [Samba] Nmbd is using the wrong ip address as source





On Sun, 2008-10-05 at 18:35 +0300, Teodor Iacob wrote: 

Does anybody have a suggestion for another list or forum to address

this issue?





> -----Original Message-----

> From: Teodor Iacob 

> Sent: 4 octombrie 2008 09:14

> To: samba at piven.org; samba at lists.samba.org

> Subject: RE: [Samba] Nmbd is using the wrong ip address as source

> 

>  

> 

> > -----Original Message-----

> > From: samba-bounces+theo=macsys.eu at lists.samba.org

> > [mailto:samba-bounces+theo=macsys.eu at lists.samba.org] On Behalf Of 

> > samba at piven.org

> > Sent: Saturday, October 04, 2008 4:41 AM

> > To: samba at lists.samba.org

> > Subject: Re: [Samba] Nmbd is using the wrong ip address as source

> > 

> > Teodor Iacob wrote:

> > > Hello,

> > > 

> > > I have a linux box with the following S/W versions:

> > > CentOS release 5.2 (Final)

> > > Linux ns.hostname.ro 2.6.18-92.1.13.el5 #1 SMP Wed Sep 24

> > 19:32:05 EDT 2008 x86_64 x86_64 x86_64 GNU/Linux

> > > Version 3.0.28-1.el5_2.1

> > > 

> > > My server has 2 IP interfaces, eth0: with the public ip

> > address and br0: for the private subnet.

> > > Br0 being a bridge ip interface between eth1 and tap0 ( for

> > openvpn ).

> > > 

> > > Now my problem is that the nmbd is doing the netbios

> > broadcasts using the eth0 ip address instead

> > > of the br0 one. I'm only interested in enabling samba on

> > the local network (br0). I have checked

> > > this by using tcpdump on another linux machine in the

> > network and saw the broadcasts with the source

> > > address the eth0 ip. Nmbd claims to win the master browsing

> > election, but in reality the windows machines

> > > ignore the election packets and another machine becomes

> > master and the browsing list is messed up..

> > > The smbd works just fine, connecting to the shares manually

> > works correctly.

> > > 

> > > How can I make nmbd to use the correct ip address? ( btw, I

> > removed the bridge config just for testing

> > > and only enabled ip on the eth1 and the same problem.. ). I

> > saw that in the previous version there was

> > > a parameter "-I" to force the source address..

> > > 

> > > For reference this is my smb.conf:

> > > [global]

> > >         workgroup = HOSTNAME

> > >         netbios name = HNS

> > >         interfaces = 10.10.10.1 127.0.0.1

> > 

> > ... why not just say "interfaces = br0" so that it binds to your 

> > private interface (which I presume owns 10.10.10.1)?  You 

> don't need 

> > to have Samba listen on the loopback address if you can 

> talk to it on 

> > another local address.

> 

> I mentioned also br0 in my quest of trying all possibilities 

> I could think of.. No change.

> But bind is only for listening, my problem is when nmbd it 

> sends packets by itself to make the election. I told you smbd 

> works fine and I can see from netstat -an at the LISTEN part 

> that it was only bound to the 10.10.10.1:139 and 10.10.10.1:445

> 

> 

> > 

> > >         hosts allow = 127.0.0., 10.10.10.

> > >         bind interfaces only = yes

> > [snip]

> > >         remote announce = 10.10.10.255/HOSTNAME

> > >         socket address = 10.10.10.1

> > 

> > Don


First of all, thank you for your patience on volunteer attempts to help you resolve your issue (considering it is still the weekend in much of the world).

Now, can you include a portion of the tcpdump you viewed from the other machine (particularly the part where the wrong address is appearing).  Also, I am assuming you have restarted both smbd and nmbd after each configuration change.

To verify that your samba settings are being read properly, try to run "netstat -nap |grep [sn]mbd" to see which ports are open on your local machine.  Also, try running "nmblookup -B 10.10.10.255 server" to ensure that nmbd is responding to name server queries on the broadcast address.

I Googled a moment, and came up with much of the above from her - http://samba.org/~tpot/articles/multiple-interfaces.html

Let us know how it goes.

Regards,
Frank 




Thanks for the output.  

I can honestly say that I don't know why your public IP would be coming back in the tcpdump.  I will have to leave that one to greater minds than mine.  The other outputs look good except for the nmblookup failure.  I think I didn't provide enough information for you - the "server" attribute should be the name of a machine on your network (a node).  That should fix the success of that query.

Also, try to add the "-d 8" parameter to add additional debug output to this command.  It should give you a lot more information about how it is performing lookups.  If you even want to test a step further, rather than setting the "interfaces = <ip_address>" parameter in smb.conf, try to set it back to the interface name "interfaces = <ifc name, e.g. eth1>".  I recall a posting a long time ago that made references to this, so all of mine use ifc names rather than IP addresses.

Regards,
Frank





More information about the samba mailing list