4
Oracle Names

This chapter provides information about Oracle Names on Alpha OpenVMS. It covers the following topics:

• Introduction

• NAMESCTL

• Names Server Privileges

• Requirements

Introduction

The function of the Names Server is to resolve connection addresses in a homogeneous and centralized location. As a client issues a connection request, the Names Server is responsible for directing the client connection request to the appropriate listener for the specified SID. TNSNAMES.ORA can also resolve the listener address. However, the benefits of the centralized list of connection addresses that Oracle Names provides greatly eases the maintenance of large network definitions.

NAMESCTL

The NAMESCTL utility is used to start and stop the Names Server and to query its status or services. The NAMESCTL command executes the command procedure ORA_NETCONFIG:NAMESCTL.COM, which provides a shell to the executable program ORA_NETCONFIG:NAMESCTL.EXE.

The main function of the command procedure ORA_NETCONFIG:NAMESCTL.COM is to check that the privileges required to start the Names Server are present (see the section "Names Server Privileges"). If a NAMESCTL START command is entered and the required privileges are not present, an error is displayed and NAMESCTL exits.

Names Server Privileges

The process in which the Names Server runs must have the Alpha OpenVMS privileges in the table below to be able to perform the associated function.

Table 4-1 Privileges and Their Functions

Privilege	Function
CMKRNL	Facilitate kernel mode processing.
PRMMBX	Create a permanent mailbox on which to listen (The mailbox is permanent so that the logical name associated with it goes into the SYSTEM logical name table.)
SYSNAM	Create SYSTEM logical names and shared logical name tables.
TMPMBX	Create temporary mailboxes.
Note: Before attempting to start the Names Server, the process that starts the Names Server must have the privileges in this table or be able to have them set. As noted above, the NAMESCTL command file will attempt to set these privileges and warn the user if it was unable to do so.

Requirements

Before you can use Oracle Names, the following configuration files must be in the ORA.ROOT:[NETWORK.NAMES] directory of the system that calls Oracle Names:

• SDNS.ORA

SDNS.ORA

The SDNS.ORA file contains a list of preferred names servers. This file is updated to reflect the names and addresses of all the known servers that Names Server is running. The initial startup requires that SDNS.ORA identifies, at a minimum, the specifics for its own address. For example, to start a Names Server to set up at port 1575 the SNDS.ORA file should contain the following:

NAMES.PREFERRED_SERVERS =

   (ADDRESS_LIST =

       (ADDRESS =

           (PROTOCOL = TCP)

           (HOST = avms04)

           (Port = 1575)

       )

   )

The easiest way to facilitate this is to simply modify the provided SDNS_ORA.SAMPLE file to suit your purposes. Additionally, the NAMESCTL REORDER_NS will generate the SDNS.ORA file.

Optional Files

The Names Server environment can be more tightly controlled through the following (optional) files in the TNS_ADMIN directory:

• NET8.ORA

• NAMES.ORA

NET8.ORA

The NET8.ORA file is read by both the client, as part of a connection request, and by NAMESCTL, for all operations other than server startup. This file identifies the Names service to be used to resolve the connection. Within NET8.ORA, the NAMES.PREFERRED_SERVERS list specifies to the client the address of the Names Server with which to connect.

NAMES.ORA

The NAMES.ORA file describes the Names Server and is read by NAMESCTL.EXE at Server startup. NAMES.ORA identifies, among other things:

• Address of the running server

• Trace information

• Protocols serviced

• Indication of whether the network definition is stored in file format or in a database

• SID of the Names database (if applicable)