OSF DCE Administration Guide--Core Components

CDS Concepts
5. The server returns the information to the clerk on Node 1.
6. The clerk passes the requested data to the client application. The clerk also caches
the information so that it does not have to contact a server the next time a client
requests a lookup of that same name.
Figure 12-2. A Sample CDS Lookup
Cache
Node 1
Node 2
Request path
Response path
1
2
3
4
5
6
Clearinghouse
CDS
clerk
Client
application
CDS
server
12.2 Replicas and Their Contents
Directories are the units by which you distribute and replicate names throughout the
cell’s namespace. Each physical copy of a directory, including the original, is called a
replica. When you create a replica of a directory, you replicate all of the entries in it as
well.
Replicas are stored in clearinghouses. You can think of a clearinghouse as the collection
of directory replicas at a particular server. After you create a directory in one
clearinghouse, you can create replicas of it in other clearinghouses to increase
availability for looking up information. CDS periodically ensures that the contents of all
replicas of a directory remain consistent.
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