2.5. Network Services

This group contains tools to configure all kinds of services in the network. These include the name resolution, user authentication, and file services.

2.5.1. Mail Transfer Agent

This module configures your mail settings if you send your e-mail with sendmail, postfix, or the SMTP server of your provider. You can fetch mail via the fetchmail program, for which you can also enter the details of the POP3 server or IMAP server of your provider. Alternatively, use a mail program of your choice, such as KMail or Evolution, to set your POP and SMTP access data as usual (to receive mail with POP3 and send mail with SMTP). In this case, you do not need this module.

To configure your mail with YaST, specify the desired type of connection to the Internet in the first dialog of the e-mail configuration module. Choose one of the following options:


Select this option if you have a dedicated line to the Internet. Your machine is online permanently, so no dial-up is required. If your system is part of a local network with a central e-mail server, select this option to ensure permanent access to your e-mail messages.


This item is relevant for users who have a computer at home, are not located in a network, and occasionally connect to the Internet.

No Connection

If you do not have access to the Internet and are not located in a network, you cannot send or receive e-mail.

Furthermore, you can activate virus scanning for your incoming and outgoing e-mail with AMaViS by activating the respective check box. The package is installed automatically as soon as you activate the mail filtering feature. In the following dialogs, specify the outgoing mail server (usually the SMTP server of your provider) and the parameters for incoming mail. If you use a dial-up connection, specify diverse POP or IMAP servers for mail reception by various users. By means of this dialog, you can also assign aliases, use masquerading, or set up virtual domains. Click Finish to exit the mail configuration.

2.5.2. Other Available Services

Many other network modules are available in YaST.

DHCP Server

YaST can set up a custom DHCP server in only a few steps. Chapter 27, DHCP provides basic knowledge about the subject as well as a step-by-step description of the configuration process in YaST.

DNS Server

The configuration of a DNS server that is responsible for the name resolution is recommended for larger networks. Configuration with YaST is described in Section 24.1, “Configuration with YaST”. Chapter 24, The Domain Name System provides background information about DNS.

DNS and Hostname

Use this module to configure the hostname and DNS, if these settings were not already made while configuring the network devices. Also use it to change the hostname and domain name. If the provider has been configured correctly for DSL, modem, or ISDN access, the list of name servers contains the entries that were extracted automatically from the provider data. If you are located in a local network, you might receive your hostname via DHCP, in which case you should not modify the name.

HTTP Server

To run your own Web server, configure Apache with YaST. More information is available in Chapter 30, The Apache Web Server.


When booting and in small networks, hostname resolution can also be done with this module instead of using DNS. The entries in this module reflect the data of the file /etc/hosts. For more information, read Section, “ /etc/hosts.

LDAP Client

LDAP can be used instead of NIS for the user authentication in the network. Background information for LDAP and a detailed description of the client configuration with YaST are available in Chapter 29, LDAP—A Directory Service.

NFS Client and NFS Server

NFS enables you to run a file server that all members of your network can access. This file server can be used to make certain applications, files, and storage space available to users. In the NFS Server module, you can configure your host as an NFS server and determine the directories to export for general use by the network users. All users with the appropriate permissions can mount these directories in their own file trees. A description of the YaST module and background information about NFS are provided in Chapter 26, Sharing File Systems with NFS.

NIS Client and NIS Server

If you run more than one system, local user administration (using the files /etc/passwd and /etc/shadow) is impractical and requires a lot of maintenance. In this case, the user data should be administered on a central server and distributed to the clients from there. NIS is a possible solution, as are LDAP and Samba. Detailed information about NIS and the configuration with YaST is available in Chapter 25, Using NIS.

NTP Client

NTP (network time protocol) is a protocol for synchronizing hardware clocks over a network. Background information about NTP and a description of the configuration with YaST is available in Chapter 28, Time Synchronization with xntp.

Network Services (inetd)

Use this tool to determine the network services (such as finger, talk, and ftp) to start when SUSE LINUX boots. These services enable external hosts to connect to your computer. Various parameters can be configured for every service. By default, the master service that manages the individual services (inetd or xinetd) is not started.

When this module starts, choose whether to start inetd or xinetd. The selected daemon can be started with a standard selection of services. Alternatively, compose your own selection of services with Add, Delete, and Edit.

[Warning]Configuring Network Services (inetd)

The composition and adjustment of network services on a system is a complex procedure that requires a comprehensive understanding of the concept of Linux services.


With this module, you can edit the systemwide proxy settings. Detailed information about proxies can be found in Chapter 33, The Proxy Server Squid.

Administration from a Remote Host

To allow maintenance of your system over a VNC connection from a remote host, permit the establishment of connections with this YaST module. Refer to Section 3.3.2, “Clients for the VNC Installation”.


This tool is needed if you are connected to the Internet over a gateway in the local network. For DSL, the gateway data is only needed for configuring the network cards. However, the entries for DSL are merely dummies without any function.

Configuring Samba Servers and Clients

In a heterogeneous network consisting of Linux and Windows hosts, Samba controls the communication between the two worlds. Information about Samba and the configuration of clients and servers is provided in Chapter 32, Samba.

SUSE LINUX Administration Guide 9.3