Hi,
I recently switched to ubuntu for desktop and I was quite disappointed that the
autofs auto.smb script coming with the package was not working.
I spent a few hours and managed to locate the problem and find a solution, so I would like to share it.
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Problem:
Even if you setup autofs & auto.smb to properly read credential files, it does not work.
Code:
$ ls /smb/host (works fine, listing the available shares on the host, but)
$ ls /smb/host/share (goes into an endless recursion returning the list of shares. e.g.:)
$ls /smb/host/share1
/smb/host/share1/share1
/smb/host/share1/share2
...
$ ls /smb/host/share1/share1
/smb/host/share1/share1/share1
/smb/host/share1/share1/share2
...
I found that the problem in the script /etc/auto.smb.
This executes the command smbclient -gL to get the list of shares for a host.
But the script passes $1 variable (named $key in the script) which is the full host/path part.
The result is that for every host/share path the command and the script returns the list of shares on the server
and not the subdirectories of the share as it should.
Solution:
1. First configure /etc/auto.master to use auto.smb script. Here is mine:
Code:
#
# $Id: auto.master,v 1.4 2005/01/04 14:36:54 raven Exp $
#
# Sample auto.master file
# This is an automounter map and it has the following format
# key [ -mount-options-separated-by-comma ] location
# For details of the format look at autofs(5).
#/misc /etc/auto.misc --timeout=60
/smb /etc/auto.smb --timeout=30
#/misc /etc/auto.misc
#/net /etc/auto.net
Note: Uncomment any other services you want to use and set the unmount timeout to your preferences
2. Authentication setup
You may want to use different username/password/domain per server or per smb share.
smbclinet allows you to provide the username/passowrd/domain from a file called the credentials file.
The format of this file is very simple:
Code:
username = <value>
password = <value>
domain = <value>
The auto.smb script allows you one of the following options:
* A global credentials file for auto.smb, if not provided
* Looks for per share credentials file with the name host.share under the directory /etc/auto.smb.credentials
* If host.share file not found, looks for a file named as 'host' under /etc/auto.smb.credentials
Here is an example of how your /etc/auto.smb/credentials directory should look:
Code:
/etc/auto.smb.credentials/
host1
host2
host2.share1
* When you invoke ls /smb/host1/anyshare, it will get credentials from /etc/auto.smb.credentials/host1
* When you invoke ls /smb/host2/share1, , it will get credentials from /etc/auto.smb.credentials/host2.share1
* When you invoke ls /smb/host2/anyothershare, , it will get credentials from /etc/auto.smb.credentials/host2
3. The /etc/auto.smb script (make sure it is executable!):
Code:
#!/bin/bash
# $Id: auto.smb,v 1.3 2005/04/05 13:02:09 raven Exp $
# This file must be executable to work! chmod 755!
# IC patch
# The problem with the original file was that it was executing smbclient -gL $key
# But $key contains the full path e.g.: server/share/subdir
# This was causing auto.smb to go to an endless loop
# This modified file corrects this problem by passing just the host to smbclient
# and in addition it provides a simple method to locate the credentials file
# The changed parts are marked as "IC patch"
# Please read the creddir variable description to see how to provide credentials files
# Note: When you search for an inexistent share, or you authentication fails the script behaves the wrong way
# This is because smbclient does protest, it just falls back like calling it
# as smbclient -gL host
# A check at the smbclient output should be done to avoid this, but I haven't figured it out yet
# Ioannis Chronakis <i.chronakis at gmail dot com>
key="$1"
mountopts="-fstype=cifs"
smbopts=""
# IC patch
# Look for credentials files under the creddir
# If $key is just the host name, then $credfile=$creddir/$host
# If $key is in the form of host/share,
# first look for a file $creddir/$host.$share
# and it does not exist, look for $creddir/$host
creddir="/etc/auto.smb.credentials"
# IC patch
# Providing a common credfile for everything, will override the above lookup method
credfile=
# IC patch
# The problem is that the key ($1) is the full path with the host
# So there should be one key for each directory
# To solve the problem:
# Easy: Get the first part of the $1 (/host/share/...)
# Comprehensive: Look the first two (host and share)
# If key does not exist, look just for the host
host=${key%%/*}
if [[ "$key" =~ '/' ]]; then
path=${key#*/}
fi
if [ -z "$credfile" ]; then
# Search for credentials file
if [ -n "$path" ]; then
if [[ "$path" =~ '/' ]]; then
share=${path%%/*}
else
share=$path
fi
fi
# First look for $creddir/$host.$share then for $creddir/$host
if [ -n "$share" ]; then
credfile="$creddir/$host.$share"
if [ ! -e $credfile ]; then
credfile="$creddir/$host"
fi
else
credfile="$creddir/$host"
fi
fi
for P in /bin /sbin /usr/bin /usr/sbin
do
if [ -x $P/smbclient ]
then
SMBCLIENT=$P/smbclient
break
fi
done
[ -x $SMBCLIENT ] || exit 1
if [ -e $credfile ]; then
mountopts="$mountopts,credentials=$credfile"
smbopts="-A $credfile"
else
smbopts="-N"
fi
# IC patch
# Do not browse for $key, just the host part
$SMBCLIENT $smbopts -gL $host 2>/dev/null| awk -v key="$host" -v opts="$mountopts" -F'|' -- '
BEGIN { ORS=""; first=1 }
/Disk/ { if (first) { print opts; first=0 }; sub(/ /, "\\ ", $2); print " \\\n\t /" $2, "://" key "/" $2 }
END { if (!first) print "\n"; else exit 1 }
'
4. Restart autofs
You will need to restart your autofs daemon
Code:
sudo /etc/init.d/autofs restart
5. Accessing the samba shares
auto.smb will not automatically list servers under /smb.
You have to refer to them via any filesystem operation.
e.g.: ls /smb/host
This will automount the hosts shares under /smb/host
One solution will be to setup symlinks from your home directory, but be careful, when doing ls in the directory with the symlinks it will mount all the targes and this may slow down listing your directory. Better solution is to put symbolic links like those under a subdirectory.
e.g. $HOME/smb/link_to_host
6. Limitations
The script will go back to the infinite recursive behavior in the following cases:
* You try to access an inexistent share. It will list the existing shares as directory contents
* You provided wrong username or password
* The credentials file does not exist or it is not accessible
-----------------------------------
I hope this helped.
IC
