OSF DCE Administration Guide--Core Components

OSF DCE Administration Guide—Core Components
Figure 13-1. Logical and Physical Views of a Namespace
/.:/subsys
/.:/subsys/PrintQ
/.:
/.:/NY_CH
/.:/subsys
/.:/subsys/Print1
/.:/subsys/PrintQ
/.:/subsys/PrintQ/server1
/.:/subsys/PrintQ/server2
/.:/Paris_CH
= Replica
= Object entry
= Child pointer
= Soft link
LEGEND:
/.:/NY_CH
Node 1
Node 2
/.:/Paris_CH
/.:
/.:/subsys/PrintQ
/.:
/.:/subsys
To discover the physical location of a resource, CDS looks up an attribute that is
associated with its name. Figures 13-2 through 13-4 illustrate the connection between
the various kinds of CDS names and the resources that they describe. The figures are
based on the namespace in Figure 13-1. All of the names in Figures 13-2 through 13-4
are in the same cell namespace, as evidenced by the use of the /.: prefix to represent the
cell root. (See Chapter 22 for information about name resolution across multiple cells.)
Figure 13-2 shows the relationship between two clearinghouse object entries and the
clearinghouses that they describe. A clearinghouse object entry differs from other kinds
of object entries in that it is created, used, and maintained by the CDS software instead
of by a client application. However, it is like any other object entry in that it describes a
physical resource in the network: the clearinghouse. CDS creates the object entry
automatically when you create and name the clearinghouse.
Figure 13-2 shows two clearinghouse object entries: /.:/Paris_CH, which points to the
clearinghouse that is named /.:/Paris_CH on Node 1, and /.:/NY_CH, which points to
the clearinghouse that is named /.:/NY_CH on Node 2. Each clearinghouse object entry
has an attribute called CDS_CHLastAddress attribute, whose Tower subattribute
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