Troubleshooters.Com's Linux Library Presents

Troubleshooting Samba
Presented to LEAP-CF 9/16/1999
by Steve Litt

This presentation has no warrantee, express or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. The entire risk as to the quality and performance of the presentation is with you.

Samba is a File (and print) Server

Samba is Never a Black Box

comp.protocols.smb

The Simplest Possible smb.conf

encrypt passwords=yes
netbios name=servername
workgroup=WinWorkgroupname

[homes]

Card Trick

Quick Split: Karate Kid Samba Troubleshooting

He can't fight if he can't breath
He can't browse on Network Neighborhood if he can't browse from the Windows command line.

net view \\machinename

He can't browse from the Windows Command line if he can't access from the Windows command line.

net view \\machinename
net use * \\serverIP\sharename

He can't access from the Windows command line if he can't access from the Linux command line.

net use * \\serverIP\sharename
smbclient '//serverIP/sharename -Uusername

He can't access from the Windows command line if he can't ping.

net use * \\serverIP\sharename
ping serverIP

He can't access from the Linux command line if his smb.conf is wrong.

smbclient '//serverIP/sharename -Uusername
testparm

He (usually) can't access from the Linux command line if he can't ping.

smbclient '//serverIP/sharename
ping serverIP

He can't use names if he can't resolve names

Use IP addresses until other Samba problems have been resolved.

Troubleshooting Tactics Specially Suited to Samba

How can I narrow it down just one more time?
Create a New Test Point
Small Subset Symptom Reproduction
Exploit the differences

DIAGNOSIS.txt

Included with the Samba distribution, this is a predefined diagnostic created by Andrew Tridgell. Ideal quick section, and accepted form of Samba diagnostic information transfer.

Troubleshooting Samba Printer Problems

He can't print from Win apps without a Win printer def.
He can't assign a Win printer def to a Samba printer if Win can't see his Samba printer.

net use lpt8:\\serverIP\printername
copy con: lpt8:

He can't print to Samba if his print command= won't work in Linux

testparm
Run the print command= on the command line
print command=cp %s /var/spool/samba/%p.tst;echo %s >> %p.tst;rm %s

He can't print to Samba if he can't access Samba

net view \\serverIP

He can't print to Samba if he can't print locally through Linux

lpr -P printcapprintername /etc/smb.conf
echo ^L | lpr -P printcapprintername

Printing hint: Always make sure your printing= global option is set correctly. Option BSD works quite well in Linux.

Samba Troubleshooting Tools

Non Destructive Tools

`net view /workgroup:workgroupname`	Force a browser election on the server.
`net view \\serverIP`	Test browseability on the client. Deduce whether failure to appear on network neighborhood is due to quirky Windows Explorer.
`net use * \serverIP\sharename`	From client, access a share regardless of browseability.
`net use lpt8: \\serverIP\printcapPrinterName`	Anything copied to lpt8: is routed to the Samba printer
net use	Show all Samba resources used by the Win client.
`smbclient '//serverIP/sharename' -Uusername`	From a Linux box or the server, access a share regardless of browseability.
`smbclient -NL serverIP`	From Linux box, browse all browseable server resources.
`ping serverIP`	Test connectivity to rule out connectivity causes.
`tail -f log.nmb`	Watch nmbd log entries in real time.
`tail -f log.smb`	Watch smbd log entries in real time.
`testparm`	Test smb.conf for legality of entries View Global Defaults View all settings for Samba server
SWAT	Current Settings Default Settings Available Settings Primary Synonyms One Click HTML Help View Connection, Share and File Activity WARNING: Never go in as root unless you really want to change something. Even then, always back up before going in as root. WARNING: SWAT can be a security problem, especially as root.
`man smb.conf`	Ultimate authority on substitution chars, commands, etc.

Server-Changing Tools

`/etc/rc.d/init.d/smb restart`	Restart Samba. Although not all smb.conf changes require a restart to be effective, restart always to start from a known state.
Tiny smb.conf	Verify that Samba itself is working. Create a tiny setup whose every line serves to reproduce a problem and/or exploit differences.
Change workgroup name	Reproduce browser timing problems on a Windows client. The client "remembers" workgroup names between sessions.
Make new share	New share can reproduce the symptom, or fail to exhibit the symptom. One of each enables exploitation of differences.
Make your own log file	Use preexec= and postexec=, with substitution variables and echo commands. May need to use root preexec= and root postexec=.
Make your own print command=	Find out what Windows is sending to the printer.