OSF DCE Administration Guide--Core Components

OSF DCE Administration Guide—Core Components
other daemons or processes. Occasionally however, you may need to manually start or
restart this daemon.
The dced program comprises a set of DCE host services that satisfies many needs of
DCE client and server applications on a host system:
• The endpoint mapper service acts as a directory of servers running on a host. Clients
can acquire a registered server’s communication endpoint by looking in the host
endpoint map.
• A security validation service manages DCE security on the local host.
• A server configuration and execution service lets adminitrators remotely set servers’
starting and stopping conditions, explicitly start and stop individual servers, and
monitor running servers’ states.
• A key management service lets administrators manage server passwords remotely.
• A hostdata service lets administrators remotely manage data stored in files on a host.
Administrators will find this most useful for remotely managing a host’s cell name
and cell alias information.
• An attribute schema capability lets administrators add new attributes to server
configuration information.
Normally, any system that hosts a DCE server (such as a DCE cell directory server) or
that runs a DCE-based application server or client that uses authentication, must also run
the dced process.
It is clear that if the dced process failed for some reason, it would take all of its
component services down along with it, leaving the host unable to respond to client
requests. Similarly, a failure of one of the component services (for example the key
management service) might be caused by the dced process unexpectedly exiting for
some reason. This relationship between dced and its component services is worth
remembering if problems occur.
9.2 Starting and Stopping DCE Host Services
Although the dced process generally starts as part of the host booting process, sometimes
you may need to start the process manually.
Before starting dced, any underlying network services on which client/server
communication depends must be available; on most UNIX systems, for example,
network interfaces and routing services must be enabled. Once these transport-layer
services are established, you can start dced. After dced starts, RPC-based servers can
start.
The endpoint mapper listens on privileged or reserved communication ports (well-known
endpoints) for client requests for service. Consequently, dced must be started as a
privileged user.
Part of dced (the endpoint map) contains information that clients use to locate servers on
a host system. The dced process maintains a copy of this information in a database file
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