Chapter 28. Time Synchronization with xntp / 28.3. Configuring an NTP Client with YaST | ||||
|---|---|---|---|---|
 | 28.2. Setting Up a Local Reference Clock | Chapter 29. LDAP—A Directory Service |  | |
Chapter 28. Time Synchronization with xntp / 28.3. Configuring an NTP Client with YaST | ||||
|---|---|---|---|---|
| 28.2. Setting Up a Local Reference Clock | Chapter 29. LDAP—A Directory Service | | |
As well as this manual configuration of xntp, SUSE LINUX facilitates the configuration of an NTP client with YaST. Use the easy quick configuration or complex configuration. Both are described in the following.
The easy NTP client configuration comprises two dialogs. Set the start mode of xntpd and the server to query in the first dialog. To start xntpd automatically when the system is booted, click . Then click to access a second dialog in which to select a suitable time server for your network.
In the detailed server selection dialog, determine whether to implement time synchronization using a time server from your local network or an Internet-based time server that takes care of your time zone (). For a local time server, click to start an SLP query for available time servers in your network. Select the most suitable time server from the list of search results and exit the dialog with . For a public time server, select your country (time zone) and a suitable server from the list under then exit the dialog with . In the main dialog, test the availability of the selected server with and quit the dialog with .
The complex configuration of an NTP client can be accessed under from the main dialog of the module, shown in Figure 28.1, “YaST: Configuring an NTP Client”, after selecting the start-up mode as described in the quick configuration.
In , determine whether xntpd should be started in a chroot jail. This increases the security in the event of an attack over xntpd, because it prevents the attacker from compromising the entire system. sets up the NTP client to get a list of the NTP servers available in your network via DHCP.
The servers and other time sources for the client to query are listed in the lower part. Modify this list as needed with , , and . provides the possibility to view the log files of your client or tune the firewall to the NTP client configuration.
Click to add a new source of time information. In the following dialog, select the type of source with which the time synchronization should be made. The following options are available:
Another dialog enables you to select an NTP server (as
described in Section 28.3.1, “Quick NTP Client Configuration”).
Activate
to trigger the synchronization of the time
information between the server and the client when the system is booted.
An input field allows you to specify additional options
for xntpd. Refer to /usr/share/doc/packages/xntp-doc
for detailed information.
A peer is a machine to which a symmetric relationship is established: it acts both as a time server and as a client. To use a peer in the same network instead of a server, enter the address of the respective system. The rest of the dialog is identical to the dialog.
To use a radio clock in your system for the time
synchronization, enter the clock type, unit
number, device name, and other options in this dialog.
Click to fine-tune the driver.
Detailed information about the operation of a local radio clock
is available in
/usr/share/doc/packages/xntp-doc/html/refclock.htm.
Time information and queries can also be transmitted via broadcast in the network. In this dialog, enter the address to which such broadcasts should be sent. Do not activate broadcasting unless you have a reliable time source like a radio controlled clock.
If you want your client to receive its information via broadcast, enter the address from which the respective packets should be accepted in this fields.
