Mastering Samba on Linux: Install, Configure, and Manage File Sharing

Table of Contents

1. Fundamentals

1.1 Introduction to Samba Service

In 1987 Microsoft and Intel defined the SMB (Server Message Block) protocol to simplify file and printer sharing within LANs. In 1991 a university student, Tridgwell, created the SMBServer program based on SMB to enable file sharing between Linux and Windows systems.

Required packages: Samba server package Samba-client client package Samba-common common files package

Samba consists of two daemon processes: smbd and nmbd, each started independently.

nmbd

Start script: /etc/rc.d/init.d/nmb Provides NetBIOS name service for CIFS‑based sharing environments

NetBIOS name service is a Windows host‑communication mechanism; CIFS is generally preferred

Listens on UDP port 137 (UCP protocol)

smbd

Start script: /etc/rc.d/init.d/smb Handles file and printer sharing, user authentication, and file locking

Listens on TCP ports 139 and 445

1.2 Installing Samba Service

[root@localhost ~]# yum install samba
Loaded plugins: langpacks, product-id, subscription-manager
…
Installing:
samba x86_64 4.1.1-31.el7
Transaction Summary
================================================================================
Install 1 Package
samba.x86_64 0:4.1.1-31.el7
Complete!

2. Samba Main Configuration File

The main configuration file of Samba is similar to Apache's, containing global parameters that affect all shares and section parameters that affect individual shares. Custom shares are defined in the file.

Main configuration file:

/etc/samba/smb.conf

2.1 Global Settings

Global settings define the overall sharing environment and apply to every defined share.

2.2 Private Home Directories

Settings that prevent sharing of user home directories

2.3 Printer Sharing

Settings that enable sharing of printer devices

2.4 Custom Shares

Settings for user‑defined shared resources

3. Samba Command‑Line Tools

smbclient

– interactive data access smbpasswd – manage Samba account passwords pdbedit – edit the SMB account database testparm – test configuration syntax and display effective settings

3.1 smbclient Command

Notes: smbclient can specify username and password directly or interactively

List all shares of a host: smbclient -L HOST -U USERNAME Access a specific share:

smbclient //SERVER/shared_name -U USERNAME

# 1. List shares on an IP address
smbclient -L 198.168.0.1 -U username%password

# 2. Use smbclient like an FTP client (cd, lcd, get, put, mput, etc.)
smbclient //192.168.0.1/tmp -U username%password

# 3. Run a single command
smbclient -c "ls" //192.168.0.1/tmp -U username%password
smbclient //192.168.0.1/tmp -U username%password
smb:/>ls

# 4. Mount remote share via mount or smbcount
mount -t cifs -o username=escape,password=123456 //192.168.0.1/tmp /mnt/tmp
umount /mnt/tmp

3.2 smbpasswd Command

Samba uses separate passwords from the system accounts. The smbpasswd command adds or changes a Samba password for a system user.

[root@localhost ~]# smbpasswd -a escape

3.3 pdbedit Command

pdbedit

manages the SMB account database. Use the -a option when adding a new account.

[root@localhost ~]# pdbedit -a escape

4. Practical Demonstration

4.1 Server Configuration

Step 1: Create Samba user account

Samba uses user‑mode authentication; the account must exist on the system.

Create the account in the Samba database:

[root@localhost ~]# id escape
uid=1000(escape) gid=1000(escape) groups=1000(escape)

[root@localhost ~]# pdbedit -a -u escape
new password: ********
retype new password: ********
Unix username: escape
…

Step 2: Create shared directory

Consider file permissions and SELinux context.

Set SELinux context for the share:

[root@localhost ~]# mkdir /home/database
[root@localhost ~]# chown -Rf escape:escape /home/database

[root@localhost ~]# semanage fcontext -a -t samba_share_t /home/database
[root@localhost ~]# restorecon -Rv /home/database
restorecon reset /home/database context unconfined_u:object_r:home_root_t:s0->unconfined_u:object_r:samba_share_t:s0

Step 3: Configure SELinux policies

Enable Samba to access user home directories:

# getsebool -a | grep samba
… (list of samba booleans, all off) …
# setsebool -P samba_enable_home_dirs on

Step 4: Edit /etc/samba/smb.conf

# vim /etc/samba/smb.conf
[global]
    workgroup = MYGROUP
    server string = Samba Server Version %v
    log file = /var/log/samba/log.%m
    max log size = 50
    security = user
    passdb backend = tdbsam
    load printers = yes
    cups options = raw
[database]
    comment = Do not arbitrarily modify the database file
    path = /home/database
    public = no
    writable = yes

Step 5: Restart Samba services

# systemctl restart smb
# systemctl enable smb
ln -s '/usr/lib/systemd/system/smb.service' '/etc/systemd/system/multi-user.target.wants/smb.service'

# iptables -F
# service iptables save
iptables: Saving firewall rules to /etc/sysconfig/iptables: [ OK ]

4.2 Windows Client

Samba solves resource‑sharing problems between Linux and Windows systems.

Access a share by entering \\SERVER_IP in the Windows Run dialog.

If the Linux firewall rules are cleared, the Samba login screen appears.

Enter the Samba username (e.g., escape) and the password set with pdbedit to log in.

4.3 Linux Client

Samba also enables file sharing between Linux systems.

Install the client package cifs-utils:

# yum install cifs-utils
Loaded plugins: langpacks, product-id, subscription-manager
…
Installing:
cifs-utils x86_64 6.2-6.el7
Transaction Summary
================================================================================
Install 1 Package
cifs-utils.x86_64 0:6.2-6.el7
Complete!

Create an authentication file with Samba credentials and restrict its permissions:

# vim auth.smb
username=escape
password=redhat
domain=MYGROUP

# chmod 600 auth.smb

Add a mount entry to /etc/fstab so the share persists after reboot:

# mkdir /database
# vim /etc/fstab
…
//192.168.10.10/database /database cifs credentials=/root/auth.smb 0 0

# mount -a

Or mount manually:

# mount -t cifs //SERVER/shared_name /mount_point -o username=USERNAME,password=PASSWORD

After mounting, files created from Windows appear in /database and can be edited on Linux.

# cat /database/Memo.txt
i can edit it .