14.2. Samba Daemons and Related Services
The following is a brief introduction to the individual Samba daemons and services, as well as details on how to start and stop them.
14.2.1. Daemon Overview
Samba is comprised of three daemons (smbd, nmbd, and winbindd). Two services (smb and windbind) control how the daemons are started, stopped, and other service-related features. Each daemon is listed in detail, as well as which specific service has control over it.
14.2.1.1. The smbd daemon
The smbd server daemon provides file sharing and printing services to Windows clients. In addition, it is responsible for user authentication, resource locking, and data sharing through the SMB protocol. The default ports on which the server listens for SMB traffic are TCP ports 139 and 445.
The smbd daemon is controlled by the smb service.
14.2.1.2. The nmbd daemon
The nmbd server daemon understands and replies to NetBIOS name service requests such as those produced by SMB/CIFS in Windows-based systems. These systems include Windows 95/98/ME, Windows NT, Windows 2000, Windows XP, and LanManager clients. It also participates in the browsing protocols that make up the Windows Network Neighborhood view. The default port that the server listens to for NMB traffic is UDP port 137.
The nmbd daemon is controlled by the smb service.
14.2.1.3. The winbindd daemon
The winbind service resolves user and group information on a Windows NT server and makes it understandable by UNIX platforms. This is achieved by using Microsoft RPC calls, Pluggable Authentication Modules (PAM), and the Name Service Switch (NSS). This allows Windows NT domain users to appear and operate as UNIX users on a UNIX machine. Though bundled with the Samba distribution, the winbind service is controlled separately from the smb service.
The winbindd daemon is controlled by the winbind service and does not require the smb service to be started in order to operate. Because winbind is a client-side service used to connect to Windows NT based servers, further discussion of winbind is beyond the scope of this manual.
14.2.2. Starting and Stopping Samba
To start a Samba server, type the following command in a shell prompt while logged in as root:
/sbin/service smb start |
 | Important |
|---|---|
To set up a domain member server, you must first join the domain or Active Directory using the net join command before starting the smb service. |
To stop the server, type the following command in a shell prompt while logged in as root:
/sbin/service smb stop |
The restart option is a quick way of stopping and then starting Samba. This is the most reliable way to make configuration changes take effect after editing the configuration file for Samba. Note that the restart option starts the daemon even if it was not running originally.
To restart the server, type the following command in a shell prompt while logged in as root:
/sbin/service smb restart |
The condrestart (conditional restart) option only starts smb on the condition that it is currently running. This option is useful for scripts, because it does not start the daemon if it is not running.
 | Note |
|---|---|
When the smb.conf file is changed, Samba automatically reloads it after a few minutes. Issuing a manual restart or reload is just as affective. |
To conditionally restart the server, type the following command as root:
/sbin/service smb condrestart |
A manual reload of the smb.conf file can be useful in case of a failed automatic reload by the smb service. To ensure that the Samba server configuration file is reloaded without restarting the service, type the following command as root:
/sbin/service smb reload |
By default, the smb service does not start automatically at boot time. To configure Samba to start at boot time, use an initscript utility, such as /sbin/chkconfig, /sbin/ntsysv, or the Services Configuration Tool program. Refer to the chapter titled Controlling Access to Services in the Red Hat Enterprise Linux System Administration Guide for more information regarding these tools.