OSF DCE Administration Guide--Core Components

OSF DCE Administration Guide—Core Components
Clerk
Clerk
M
U
X
TP
M
U
X
Modem
Modem
Site 1
( Time −Provider )
Site 2
Global/
Courier
Server
Clerk
Modem
Modem
Clerk
Site 3
Site 4
Global
Server
Global
Server
Many of the same recommendations for a LAN with WAN links also apply to the
network that does not have any LANs. Keep the following considerations in mind when
planning your all-WAN network:
• The network should have at least three servers, preferably four or more.
• Every server should be configured as a global server.
• Couriers are not required; however, you can configure any or all of the servers as
couriers. The minservers attribute will force each global server to synchronize with
at least two others.
• You can place the servers anywhere in the network, but place at least one at the
central site; choose the most active remote nodes that are connected by the most
reliable links for the rest of the servers.
• If you are using time-providers, which are recommended for this type of network,
connect one to a global server node at the central site.
In a geographically distributed WAN network, also consider ease of access to the nodes
by system managers or service personnel. If you locate a server at one of two nodes
where traffic patterns and link reliability are equal, locate the server at the node that is
convenient to your central site or management facility.
24.6 Planning for External Time-Providers
To closely synchronize your systems with UTC, you can place one or more time-
providers in your network. Time-providers have many forms; they can be radio
receivers, software/modem combinations, or satellite receivers. (See the for additional
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