Pogoplug: Installing Samba v3.6

Assuming you have read many of the other blogs, wikis, etc out there you will notice that many of them do not take security into consideration, which tends to drive me nuts. They also mention that you will need a swap file to run version 3 of Samba; however, that is not completely true. The fact is, you can run Samba v3 without a swap file (or swap partition) as long as you do not install any other services (e.g. FTP, Apache, etc). I will include instructions on how to make a swap file and add it to your rcS configuration file:

How to create a swap file:

1. Use SSH and login into your Pogoplug
2. /opt/bin/ipkg install e2fslibs
3. dd if=/dev/zero of=/tmp/.cemnt/mnt_sda1/swapfile.img bs=1M count=512 #for a 1GB swapfile, use count=1024
4. /opt/sbin/mkswap /tmp/.cemnt/mnt_sda1/swapfile.img
5. /opt/sbin/swapon /tmp/.cemnt/mnt_sda1/swapfile.img
6. /opt/bin/nano /etc/init.d/rcS
7. Add the line from step 4 before Samba starts up (if already installed) or at the end, and save the file.
8. Exit out of nano after saving

A few notes about the swap file:

• I would highly recommend creating the swap file on an actual hard drive and not on flash memory (aka USB or flash drives), because swap files may prematurely exhaust your flash drive's limited write cycles.
• 512MB swap file should be more than ample, due to the fact that that the Pogoplug's RAM is only 128MB and having it at 1GB will not provide any additional benefit.

How to install Samba v3.6:

Assuming you are still in the same SSH session, if not reconnect and login as root, please follow these instructions a precisely as you can. I am working on the assumption that you have already formatted your hard drives as ext3 (except for the ext2 system drive that you use to install your Optware packages in /opt); if not then, I would recommend searching for sites with info on how to do that. The reason for ext3 is the journaling feature that helps reduce the risk of data corruption in the event of a power outage. I am also assuming that you have already added users to your your Pogoplug via the adduser command and have configured their home directories to be as such: /tmp/.cemnt/mnt_sda1/user1 in the /etc/passwd file. The reason for this to not only simplify the administration of Samba, but to also increase security to a limited degree. 

• /opt/bin/ipkg install samba36
• Once it is installed, you will now have to configure using your favorite text editor, I prefer nano, but feel free to use which ever one you like: /opt/bin/nano /opt/etc/samba/smb.conf
• You can copy and paste the configuration file below; however, please edit the entries to match your Pogoplug's configuration:

# sample samba 3.0 conf file

[global]

log level = 1

log file = /opt/var/log/samba/log.%m

printcap name = /dev/null

load printers = no

printing = bsd

# CHANGE these settings to match your network/workgroup setup

# ------------------

workgroup = WorkgroupName

server string = ServerName

# netbios name = usbdrive

# your wins server ip address

# wins server = 10.0.0.1

# the networks you want to allow connections from

hosts allow = 127.0.0.1 192.

hosts deny = 0.0.0.0/0

# ------------------

config file=/opt/etc/samba/smb.conf

os level = 8

load printers = no

max log size = 10

security = user

encrypt passwords = yes

smb passwd file = /opt/etc/samba/smbpasswd

socket options = TCP_NODELAY SO_KEEPALIVE SO_SNDBUF=16384 SO_RCVBUF=16384

preferred master = no

local master = yes

dns proxy = no

preserve case = yes

short preserve case = yes

default case = upper

case sensitive = no

mangled names = yes

# null passwords = yes

# username map =

dos filetimes = yes

force directory mode=771

force create mode=660

create mask=771

# map system=yes

map to guest=Bad User

guest account = root

guest ok = no

bind interfaces only = yes

# interfaces = ixp0 lo

winbind use default domain = no

[user1]

path = /tmp/.cemnt/mnt_sda1/user1

valid users = user1

public = no

writable = yes

• Save the file and exit out of the text editor.
• Edit the rcS file with your favorite text editor (e.g. /opt/bin/nano /etc/init.d/rcS) and add the following lines in the order as they appear:

sleep 20
mount -o exec,remount /tmp/.cemnt/mnt_sda1
mount /tmp/.cemnt/mnt_sda1 /opt
/opt/sbin/swapon /tmp/.cemnt/mnt_sda1/swapfile.img
/opt/etc/init.d/S08samba start

• Save the file and exit out of the text editor. This will make sure that your Pogoplug will start your swap file and Samba services every time it boots.
• to start Samba, just type in the following command: /opt/etc/init.d/S08samba start
• Add user accounts to Samba that are stated within the smb.conf file by issuing the following command with the corresponding user account name followed by the user's password:  /opt/bin/smbpasswd -a username

Troubleshooting Samba v3.6:

If you are running into problems with your Samba shares, it will likely be due to on of the following issues:

1. Misconfiguration in the smb.conf file
2. Failed to use an Ext2 or Ext3 (Recommended) file system for your Samba shares
3. Failed to apply the proper permissions (remember the configuration above is meant for user security)
4. If you have problems editing your /etc/init.d/rcS file (e.g. read-only file system) try this command: mount -o remount,rw /
5. Your drive has data corruption, which can be resolved by logging in as root and running the following command on the affected drive: (ext2) /opt/sbin/e2fsck /tmp/.cemnt/sda1 for (ext3) /opt/sbin/e2fsck -t /tmp/.cemnt/sda1

For problem 1, check your log files and verify that everything is correct. One common mistake is not taking into account that your Pogoplug may have your users shares on  /tmp/.cemnt/mnt_sdb1 instead of sda1. As they say Google is your friend.

For problem 2, you can either search for instructions on how to create an Ext3 partition, or you can connect your drive to your Windows computer and format it with Ext3 using the EaseUS Partition Master Home Edition software, which happens to be free :-)

For problem 3, which happens to be a very common issue. First check your permissions on each user's shared directory (e.g.  /tmp/.cemnt/mnt_sda1/user1) and verify that they have the following permissions, like the example below by peforming ls -l /tmp/.cemnt/mnt_sda1/ command:

drwxr-xr-x    4 user1  1000          4096 Nov 10 12:00 user1

If it says root for the user-id and you do not have at least 700 permissions (e.g. drwxr------), then perform the following commands for each user (you can find the user's group numbers in /etc/passwd):

chmod 700 /tmp/.cemnt/mnt_sda1/user1

chown user1 /tmp/.cemnt/mnt_sda1/user1

chgrp 1000 /tmp/.cemnt/mnt_sda1/user1