How to Share Files Over Samba on Arch Linux

Samba is a powerful open-source implementation of the SMB/CIFS networking protocol, which allows file and printer sharing between computers running Windows and Unix-like systems such as Linux. On Arch Linux, configuring Samba is straightforward once you understand the basic components and steps. In this guide, we’ll walk through how to install, configure, and secure Samba for file sharing on Arch Linux.

1. Introduction to Samba

Samba is a suite of tools that enables Unix-based systems to interact with Windows systems in a networked environment. It allows for:

• File sharing between Linux and Windows machines
• Sharing printers across a network
• Acting as a domain controller (optional)
• Authentication and access control using user accounts

Arch Linux doesn’t come with Samba pre-installed, so you’ll need to install and configure it manually.

2. Installing Samba on Arch Linux

Begin by installing the samba package from the official repositories.

sudo pacman -S samba

This installs the Samba server (smbd), the NetBIOS name server (nmbd), and associated tools.

To verify the installation, check the version:

smbd --version

3. Creating a Shared Directory

You can share any directory over the network. For this example, we’ll create a directory called shared under /srv.

sudo mkdir -p /srv/samba/shared
sudo chown nobody:nogroup /srv/samba/shared
sudo chmod 0775 /srv/samba/shared

Explanation:

• nobody:nogroup ensures the directory can be accessed without a dedicated user.
• 0775 gives read/write access to the owner and group, and read/execute to others.

You can tailor permissions based on your needs.

4. Configuring the Samba Server

Samba uses a configuration file located at /etc/samba/smb.conf. Start with a backup:

sudo cp /etc/samba/smb.conf.default /etc/samba/smb.conf

Then open the file with your preferred text editor:

sudo nano /etc/samba/smb.conf

Here’s a minimal example to share the shared directory with guest access:

[global]
   workgroup = WORKGROUP
   server string = Samba Server %v
   netbios name = archlinux
   security = user
   map to guest = Bad User
   dns proxy = no

[Shared]
   path = /srv/samba/shared
   browsable = yes
   writable = yes
   guest ok = yes
   read only = no
   create mask = 0664
   directory mask = 0775

Explanation:

• workgroup should match the workgroup of your Windows machines.
• security = user allows user-based authentication.
• guest ok = yes allows unauthenticated access (you can disable this for more security).

Save and exit.

5. Creating Samba Users

If you want to restrict access to authenticated users (recommended for private networks), you’ll need to create Samba users.

Step 1: Create a system user (if not already present)

sudo useradd -M -d /srv/samba/shared -s /usr/bin/nologin sambauser
sudo passwd sambauser

Step 2: Add the user to Samba’s password database

sudo smbpasswd -a sambauser

Then enable the user:

sudo smbpasswd -e sambauser

Make sure the shared directory is owned by this user if you disable guest access:

sudo chown sambauser:sambauser /srv/samba/shared

Update your smb.conf file accordingly:

[Shared]
   path = /srv/samba/shared
   browsable = yes
   writable = yes
   valid users = sambauser
   read only = no

6. Starting and Enabling the Samba Services

Samba uses two main services:

• smbd: Handles file sharing
• nmbd: Handles NetBIOS name resolution (optional but useful)

Enable and start the services:

sudo systemctl enable --now smb.service
sudo systemctl enable --now nmb.service

Check the status:

systemctl status smb.service
systemctl status nmb.service

7. Adjusting the Firewall

If you use ufw, open the required ports:

sudo ufw allow 'Samba'

Alternatively, with iptables:

sudo iptables -A INPUT -p tcp -m multiport --dports 137,138,139,445 -j ACCEPT
sudo iptables -A INPUT -p udp -m multiport --dports 137,138,139,445 -j ACCEPT

Make sure to persist the rules if you use iptables.

8. Accessing the Samba Share

From Linux

You can access Samba shares using smbclient or mount them directly:

Install the client tools (if not already installed):

sudo pacman -S smbclient gvfs-smb

Then access:

smbclient //archlinux/Shared -U sambauser

Or mount using mount:

sudo mount -t cifs //archlinux/Shared /mnt -o username=sambauser

From Windows

1. Open File Explorer.
2. In the address bar, enter: \\archlinux\Shared
3. Enter credentials if required.

Make sure the hostname archlinux resolves correctly (use IP address if necessary).

9. Securing Your Samba Shares

Security is essential when sharing files. Here are a few tips:

1. Disable Guest Access

Avoid guest ok = yes unless absolutely necessary. This prevents unauthorized access.

2. Use Firewall and VPNs

Restrict Samba access to known IPs or networks using firewall rules. Never expose Samba to the public internet directly.

3. Use Strong Passwords

Always set strong passwords for Samba users.

4. Audit and Monitor

Enable logging in smb.conf:

log file = /var/log/samba/smbd.log
max log size = 1000

Check logs periodically for suspicious activity.

5. Regular Updates

Keep your system and Samba package updated:

sudo pacman -Syu

10. Conclusion

Setting up Samba on Arch Linux gives you a versatile and powerful file sharing solution that works across platforms. Whether you’re building a home media server, setting up a workgroup file share, or simply want to access Linux files from Windows, Samba makes it all possible.

While the default setup is relatively simple, it’s crucial to tailor your configuration for security, especially if your Samba server is part of a larger or sensitive network. You can further expand the setup with advanced options like access control lists (ACLs), encrypted connections, or integration with LDAP/Active Directory.

By following the steps in this guide, you now have a functioning Samba file server on your Arch Linux system.