Chapter 34. Analysing and solving samba problems

There are many sources of information available in the form of mailing lists, RFC's and documentation. The docs that come with the samba distribution contain very good explanations of -general SMB topics such as browsing.

Diagnostics tools

+general SMB topics such as browsing.

Diagnostics tools

With SMB networking, it is often not immediately clear what +the cause is of a certain problem. Samba itself provides rather +useful information, but in some cases you might have to fall back +to using a sniffer. A sniffer is a program that +listens on your LAN, analyses the data sent on it and displays it +on the screen.

Debugging with Samba itself

One of the best diagnostic tools for debugging problems is Samba itself. You can use the -d option for both smbd and nmbd to specify what -debug level at which to run. See the man pages on smbd, nmbd and +debug level at which to run. See the man pages on smbd, nmbd and smb.conf for more information on debugging options. The debug level can range from 1 (the default) to 10 (100 for debugging passwords).

@@ -24,14 +29,19 @@ typing in your password, you can attach gdb and continue.

Some useful samba commands worth investigating:

-	$ testparm | more
-	$ smbclient -L //{netbios name of server}
-

-An SMB enabled version of tcpdump is available from -http://www.tcpdup.org/. -Ethereal, another good packet sniffer for Unix and Win32 -hosts, can be downloaded from http://www.ethereal.com. -

+$ testparm | more +$ smbclient -L //{netbios name of server} +

Tcpdump

Tcpdump was the first +unix sniffer with SMB support. It is a command-line utility and +nowadays, it's SMB support is somewhat less then that of ethereal +and tethereal.

Ethereal

+Ethereal is a graphical +sniffer, available for both unix (Gtk) and Windows. Ethereal's +SMB support is very good.

For details on the use of ethereal, read the well-written +ethereal User Guide.

+Listen for data on ports 137, 138, 139 and 445. E.g. +use the filter port 137 or port 138 or port 139 or port 445.

A console version of ethereal is available as well and is called +tethereal.

The Windows Network Monitor

For tracing things on the Microsoft Windows NT, Network Monitor (aka. netmon) is available on the Microsoft Developer Network CD's, the Windows NT Server install CD and the SMS CD's. The version of @@ -41,7 +51,7 @@ The version on the NT Server install CD will only allow monitoring of network traffic directed to the local NT box and broadcasts on the local subnet. Be aware that Ethereal can read and write netmon formatted files. -

Installing 'Network Monitor' on an NT Workstation or a Windows 9x box

Installing 'Network Monitor' on an NT Workstation

Installing netmon on an NT workstation requires a couple of steps. The following are for installing Netmon V4.00.349, which comes with Microsoft Windows NT Server 4.0, on Microsoft Windows NT @@ -74,17 +84,17 @@ Now copy the files from the NT Server in %SYSTEMROOT%\Syste to %SYSTEMROOT%\System32\netmon\*.* on the Workstation and set permissions as you deem appropriate for your site. You will need administrative rights on the NT box to run netmon. -

+

`Installing 'Network Monitor' on an 9x Workstation`

To install Netmon on a Windows 9x box install the network monitor agent from the Windows 9x CD (\admin\nettools\netmon). There is a readme file located with the netmon driver files on the CD if you need information on how to do this. Copy the files from a working Netmon installation. -

`Useful URLs`

See how Scott Merrill simulates a BDC behavior at +

`Useful URLs`

See how Scott Merrill simulates a BDC behavior at http://www.skippy.net/linux/smb-howto.html.
FTP site for older SMB specs: - ftp://ftp.microsoft.com/developr/drg/CIFS/

`Getting help from the mailing lists`

+ ftp://ftp.microsoft.com/developr/drg/CIFS/

`Getting help from the mailing lists`

There are a number of Samba related mailing lists. Go to http://samba.org, click on your nearest mirror and then click on Support and then click on Samba related mailing lists. @@ -94,10 +104,10 @@ For questions relating to Samba TNG go to It has been requested that you don't post questions about Samba-TNG to the main stream Samba lists.

If you post a message to one of the lists please observe the following guide lines : -

Always remember that the developers are volunteers, they are +
- Always remember that the developers are volunteers, they are not paid and they never guarantee to produce a particular feature at a particular time. Any time lines are 'best guess' and nothing more. -
- Always mention what version of samba you are using and what +
- Always mention what version of samba you are using and what operating system its running under. You should probably list the relevant sections of your smb.conf file, at least the options in [global] that affect PDC support.
- In addition to the version, if you obtained Samba via @@ -118,12 +128,11 @@ error messages.
- (Possibly) If you have a complete netmon trace ( the pipe to the error ) you can send the *.CAP file as well.
- Please think carefully before attaching a document to an email. Consider pasting the relevant parts into the body of the message. The samba mailing lists go to a huge number of people, do they all need a copy of your -smb.conf in their attach directory?

`How to get off the mailing lists`

To have your name removed from a samba mailing list, go to the +smb.conf in their attach directory?

`How to get off the mailing lists`

To have your name removed from a samba mailing list, go to the same place you went to to get on it. Go to http://lists.samba.org, click on your nearest mirror and then click on Support and -then click on Samba related mailing lists. Or perhaps see -here +then click on Samba related mailing lists.

Please don't post messages to the list asking to be removed, you will just be referred to the above address (unless that process failed in some way...) -

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+