OSF DCE Administration Guide--Core Components

OSF DCE Administration Guide—Core Components
Use an rpcentry unexport operation to remove server binding information as shown in
the following example. Notice that the object UUID is not removed from the server
entry unless you specify it as an option to the unexport operation.
dcecp> rpcentry unexport /.:/subsys/applications/bbs_server \
-interface {458ffcbe-98c1-11cd-bd93-0000c08adf56 1.0}
dcecp> rpcentry show /.:/subsys/applications/bbs_server
{76030c42-98d5-11cd-88bc-0000c08adf56}
10.4.2 UsingGroup Entries to Help Balance Server Workloads
When a client queries CDS for a server binding, the request includes the name of the
entry to look in for the binding. When only one server offers the client’s requested
service, CDS will return the same binding for every client request for this service. While
this model works fine for limited client requests, it can cause service bottlenecks when
many client requests converge on one server. Applications can avoid bottlenecks by
providing multiple servers to service large numbers of client requests. Server entry
names alone don’t provide a convenient way to distribute client requests evenly among
multiple servers because you’d have to explicitly direct each client to a particular server.
So CDS provides group entries as a convenient mechanism for distributing the client
load across multiple servers.
A CDS group entry gathers related servers together under a common group name. Group
entries contain members that are generally pointers to server entries, but members can
point to other group entries, too. When a client requests a binding from a group entry,
CDS returns, at random, one of the pointers contained in the group entry. If the entry
picked at random is another group entry, CDS doesn’t return that. Instead CDS goes to
that group and picks another random member, continuing until a server entry is returned.
This model requires that any group member can service the client request. Figure 10-3
shows how a group entry contains members that point to other groups and to server
entries.
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