OSF DCE Administration Guide--Core Components

OSF DCE Administration Guide—Core Components

• Is your cell a single LAN, an extended LAN, a WAN, or a combination of LANs and

WANs?

• What is the current or proposed network topology (component placement)?

• How many servers will be required? Where will they be located?

• Will global servers be required? Where will they be located?

• Will you need to conﬁgure any couriers if you are using global servers?

• Will you use an external time-provider to obtain UTC?

The following sections will help you answer these questions.

Although there are many network conﬁgurations that affect DTS planning, several

general rules apply regardless of your network conﬁguration or the number of nodes in

the network. These guidelines are summarized as follows:

• DTS must be installed with the other DCE components.

• Locate DTS servers on the same nodes as the servers for the other DCE components

wherever possible.

• Each cell should have a minimum of three DTS servers; preferably four servers to

provide redundancy.

• Each LAN should have at least one server.

• Locate the servers at the sites with the greatest number of nodes.

Although other factors must be considered when you plan your network, these factors

depend on network topology and conﬁguration. The following sections present some

typical cell arrangements to aid you in implementing DTS on your own network.

24.3 Conﬁguring DTS for a LAN

If your nodes are in a single LAN, regardless of the number of nodes, planning your DTS

implementation is relatively simple. To detect faulty time servers, conﬁgure at least

three systems as servers. If you want to provide redundancy for your DTS

implementation, plan to install four or more servers in the network. That way, if one of

the servers fails, DTS can still synchronize with reliable results.

To ensure the reliability of your DTS implementation, make sure that the network

connections between server nodes are stable. If you plan to add WAN links to your

LAN, do not move the servers to the remote nodes, since WAN links are usually less

reliable than the LAN.

If you have a single LAN, the location of the servers on the LAN is not critical. You can

locate one of the servers on a readily accessible node to aid in troubleshooting, but there

are no other recommended server locations. Neither global servers nor couriers are

required.

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