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Table of Contents
Please report bugs using Samba's Bugzilla facilities and take the time to read this file before you submit a bug report. Also, check to see if it has changed between releases, as we may be changing the bug reporting mechanism at some point.
Please do as much as you can yourself to help track down the bug. Samba is maintained by a dedicated group of people who volunteer their time, skills, and efforts. We receive far more mail than we can possibly answer, so you have a much higher chance of a response and a fix if you send us a “developer-friendly” bug report that lets us fix it fast.
If you post the bug to the comp.protocols.smb newsgroup or the mailing list, do not assume that we will read it. If you suspect that your problem is not a bug but a configuration problem, it is better to send it to the Samba mailing list, as there are thousands of other users on that list who may be able to help you.
You may also like to look though the recent mailing list archives, which are conveniently accessible on the Samba Web pages at http://samba.org/samba/.
Before submitting a bug report, check your config for silly errors. Look in your log files for obvious messages that tell you've misconfigured something. Run testparm to check your config file for correct syntax.
Have you looked through The Samba Checklist? This is extremely important.
If you include part of a log file with your bug report, then be sure to annotate it with exactly what you were doing on the client at the time and exactly what the results were.
If the bug has anything to do with Samba behaving incorrectly as a server (like refusing to open a file), then the log files will probably be quite useful. Depending on the problem, a log level of between 3 and 10 showing the problem may be appropriate. A higher level gives more detail but may use too much disk space.
To set the debug level, use the log level in your
smb.conf. You may also find it useful to set the log
level higher for just one machine and keep separate logs for each machine.
To do this, add the following lines to your main smb.conf file:
log level = 10 |
log file = /usr/local/samba/lib/log.%m |
include = /usr/local/samba/lib/smb.conf.%m |
and create a file /usr/local/samba/lib/smb.conf. where
machinemachine is the name of the client you wish to debug. In that file put any
smb.conf commands you want; for example, log level may be useful. This also allows
you to experiment with different security systems, protocol levels, and so on, on just one machine.
The smb.conf entry log level is synonymous with the parameter debuglevel that has been used in older versions of Samba and is being retained for backward
compatibility of smb.conf files.
As the log level value is increased, you will record a significantly greater level of
debugging information. For most debugging operations, you may not need a setting higher than
3. Nearly all bugs can be tracked at a setting of 10, but be
prepared for a large volume of log data.
Samba-3.x permits debugging (logging) of specific functional components without unnecessarily cluttering the log files with detailed logs for all operations. An example configuration to achieve this is shown in:
log level = 0 tdb:3 passdb:5 auth:4 vfs:2 |
max log size = 0 |
log file = /var/log/samba/%U.%m.log |
This will cause the level of detail to be expanded to the debug class (log level) passed to
each functional area per the value shown above. The first value passed to the log level
of 0 means turn off all unnecessary debugging except the debug classes set for
the functional areas as specified. The table shown in Debuggable Functions
may be used to attain very precise analysis of each SMB operation Samba is conducting.
Table 40.1. Debuggable Functions
| Function Name | Function Name |
|---|---|
| all | passdb |
| tdb | sam |
| printdrivers | auth |
| lanman | winbind |
| smb | vfs |
| rpc_parse | idmap |
| rpc_srv | quota |
| rpc_cli | acls |
If you get the message “INTERNAL ERROR” in your log files, it means that Samba got an unexpected signal while running. It is probably a segmentation fault and almost certainly means a bug in Samba (unless you have faulty hardware or system software).
If the message came from smbd, it will probably be accompanied by a message that details the last SMB message received by smbd. This information is often useful in tracking down the problem, so please include it in your bug report.
You should also detail how to reproduce the problem, if possible. Please make this reasonably detailed.
You may also find that a core file appeared in a corefiles
subdirectory of the directory where you keep your Samba log
files. This file is the most useful tool for tracking down the bug. To
use it, you do this:
$gdb smbd core
adding appropriate paths to smbd and core so gdb can find them. If you
do not have gdb, try dbx. Then within the debugger,
use the command where to give a stack trace of where the
problem occurred. Include this in your report.
If you know any assembly language, do a disass of the routine
where the problem occurred (if it's in a library routine, then
disassemble the routine that called it) and try to work out exactly
where the problem is by looking at the surrounding code. Even if you
do not know assembly, including this information in the bug report can be
useful.
Unfortunately, some UNIXes (in particular some recent Linux kernels)
refuse to dump a core file if the task has changed UID (which smbd
does often). To debug with this sort of system, you could try to attach
to the running process using
gdb smbd , where you get
PIDPID from smbstatus.
Then use c to continue and try to cause the core dump
using the client. The debugger should catch the fault and tell you
where it occurred.
Sometimes it is necessary to build Samba binary files that have debugging symbols so as to make it possible to capture enough information from a crashed operation to permit the Samba Team to fix the problem.
Compile with -g to ensure you have symbols in place.
Add the following line to the smb.conf file global section:
panic action = "/bin/sleep 90000"
to catch any panics. If smbd seems to be frozen, look for any sleep
processes. If it is not, and appears to be spinning, find the PID
of the spinning process and type:
root# gdb /usr/local/samba/sbin/smbd
then “attach `pid'” (of the spinning process), then type “bt” to get a backtrace to see where the smbd is in the call path.