Basic Environment and services after Oracle 9i and 10g Installation

The service starts background processes, which are similar to the daemon process in UNIX. When the Oracle Database Service is started, no typical Oracle process is running in the system. On the contrary, the service process waits for the initial connection from SQL * Plus, which causes a foreground process to start and create the background process of SGA in the global region of the system. When the Oracle database is closed, all created processes are terminated. However, the process is still running, waiting for the next connection request and start command. This is when we startDatabaseBut after the database instance is disabled in SQL * Plus or Oracle Enterprise Manager, The oracleservice in Windows is still in the "started" status. You must stop the Oracle service (process) in Windows to ensure that the database is not started. Of course, when the oracleservice service is stopped, you can start the database instance in other ways. There are multiple ways to implement the management of Oracle services in windows. For details, see the relevant sections below.

Oracle network listener (Net Listener) is another important service. This service must be started before the user can connect to the Oracle database. Whether the process is closed or not does not affect the connection established between the client and the database and the user's usage of the database. Take SQL * Plus as an example, when Oracle network listener service oracletnslistener before starting, start SQL * Plus and connect to the database, the system has an error message "ORA-12541: TNS: nolistener ". The cause is that the listening service is not started or the listener is damaged. When the Oracle network listener service starts SQL * Plus and connects to the database, if the oracletnslistener service is stopped, SQL * Plus can still interact with the database as long as the connection is not disconnected. Here, TNS (Transparent Network Substrate) represents the transparent network layer.

2. Available Oracle services

The Oracle services generated in Windows vary according to the installed products. In fact, this shows that the database server is closely related to the operating system it uses.

Multiple services are generated after Oracle Database 10 Gb is installed. These are required for running Oracle Database 10 Gb.

Generally, when you create a database and complete the installation, the following two main services are automatically started:

· Oracle service (Oracle Database Service)

· Oracletnslistener (Oracle Database listening service)

If Oracle Enterprise Manager Database is installed

The oracledbconsole service is automatically started. If Automatic Storage is configured

Management, then the oraclecsservice and oracleasmservice + ASM services will also appear in the service list.

Different from Oracle 10 Gb, after oracle9i is installed, 12 related services are generated. To facilitate the comparison, the following services are related to Oracle9i Database:

(1) Oracle service

Database Service. This service is created for the system identifier SID of the database instance. Sid is the name of the Database Service (such as oracleservicetest) entered during Oracle installation ). This service is mandatory and is responsible for starting database instances.

If this service is not started, an error message for the ORA-12560 appears when any Oracle tool such as SQL * Plus is used. The information content is "ORA-12560 TNS:

Protocol adapter error ", which means that the management object of the database management system is not started, that is, the database is not working. When multiple databases are installed in the system, multiple Oracle services exist, and the SID varies depending on the database. Generally, set the Service Startup type to "automatic". In this way, the service is automatically started after the computer system is started.

(2) oracletnslistener

Listener service. For example, Oracle

Orahome92tnslistener monitors and accepts connection requests from client applications. After Windows computer restarts, the service is automatically started. If the service is not started, an error message "ORA-12541 TNS: No listener" appears when you connect using the Oracle Enterprise Manager Console or some graphical tools ". However, this does not affect normal connections. For example, when SQL * Plus is started and connected in the form of sqlplus/@ net_service_name at the MS-DOS prompt, no error message is prompted. Generally, you can set the service start type to "automatic". In this way, when the computer system starts, the service starts automatically. You can also manually start the service: C:/> Net start oracletnslistener.

Note that most of the connection problems are related to listeners.

(3) oracleagent

Proxy service. This service is part of Oracle Enterprise Manager. Execute jobs and monitor Oracle service performance and listeners, databases, and Oracle HTTP

ServerAnd Oracle Applications ). The smart proxy is also capacity.

Collect static data such as planner and Performance Manager. Capacity planner and Performance

Manager is a data collection application for Oracle diagnostic packages. Generally, set the Service Startup type to "automatic". In this way, the service is automatically started after the computer system is started.

If the agent service is not started, the system cannot find the database node through oracleagent when the OEM console is started. Therefore, when you use the Enterprise Manager Console to open the console, the database cannot be displayed because the node where the database is located cannot be found. Whether the oracleagent is enabled also affects the remote connection of the database.

In the network, Oracle intelligent

Agent is an autonomous process on a remote node. As a service, the proxy and the Oracle database server reside on the same node and provide and complete the following functions:

· Provide local services or invoke services dependent on the operating system, so as to interact with the target node of local management.

· Check the event and report the queuing result event to the OEM.

· Run Oracle Enterprise Manager jobs, collect results and outputs, and queue results.

· Process data sets.

· Cancel jobs or events controlled by the console or other applications.

(4) oraclehttpserver

The Service uses the port number 3339 to start the Oracle HTTP Server for the browser-based enterprise manager and data file library. It corresponds to Apache server, that is, web

Server. It is also the required intermediate layer for running iSQL * Plus. You can set the Service Startup type to "automatic" or "Manual" based on the actual situation ". When it is set to "automatic", Oracle httpserver will automatically start with the computer; otherwise, you can start Oracle HTTP Server through "Start HTTP server powered by Apache" in the menu group.

(5) The oraclemanagementserver OMS (Oracle Management Server) Service plays a centralized management and distributed control role between the client and the management target, and works collaboratively with the agent, process Monitoring Information and job information and store the management data in the management archive.