OSF DCE Administration Guide--Core Components

DCE Application Administration
use to access that interface. The following example of a binding (shown in dcecp
syntax) indicates the server is on the host with internet address 120.101.13.157 and is
available using the User Datagram Protocol (UDP):
{nacdg_ip_udg 120.101.13.157}
When an interface identifier is available over several transports, the server entry contains
bindings (one binding for each transport). Servers can offer more than one interface.
Multiple interfaces can be available through a single endpoint. That is, different
interfaces can have the same bindings.
The lower part of the figure contains object UUIDs. Object UUIDs offer additional
information to clients; they identify specific objects or resources managed by the server.
For instance, one print server offers printers on floor 2 while another print server offers
printers on floor 1. In this case, object UUIDs let clients select printers on the
appropriate floor. In other words, object UUIDs help clients distinguish from among
otherwise identical services.
Although application servers can manage their own server entries in CDS, you may find
it more convenient (and more straightforward) to manually add, remove, or change
information in a server entry. There are four methods for managing server entries in
CDS:
• Server entry names can be hardcoded into an application. You can change server
entry information in the source code, but you need to recompile and rerun the
application before the entry names take effect.
• Server entry names can be stored as the entryname attribute of the server’s
configuration information (using the server object) where it’s accessible to the
application. This is more convenient than recompiling but, more importantly, this
method places the server’s entry name in a standard (platform independent) place
where administrators can see it too. You might need to restart an application to use
this method, however.
• Server entry names can be passed to an application through environment variables or
arguments. While these are effective methods and they are more convenient than
recompiling, they are not platform-independent. This means you might need
different approaches on different operating systems.
• Server entry names can be directly managed in CDS by using the DCE control
program’s rpcserver object. This manual method does not require recompiling or
restarting applications.
The next sections discuss how to use the rpcserver object to manually manage server
entries in CDS.
10.4.1.1 Creating a Server Entry in CDS
Often, servers will create their own entries in CDS either when they initialize or when
they are configured after installation. But sometimes, you might want to create a server
entry manually. When you create a server entry, it is empty; it doesn’t contain any
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