Three carriages to secure Oracle network connectivity

A database is a typical representative of a network database. Users can access the database over the network. Oracle database provides a variety of network interconnection schemes, including structure and driver, whose network communication structure is similar to OSI-RM, but has its own layered mechanism. That is, Oracle's network is based on a computer network that enables Oracle to achieve data sharing, data integrity control, transmission, cross operating system platforms (which can run concurrently on Linux or Microsoft's operating system platform), and data interoperability between hardware platforms.

So what protects the connectivity of Oracle networks? In short, the global database name, listener, and network service name the three carriages guarantee the connectivity of the Oracle network.

First carriage: Global database name.

Before talking about the global database name, I want to talk about this domain name first. The domain name on this is equivalent to our real life in the same number, can be in the numerous miscellaneous of the network World accurately guide us to the site we want to visit. Judging from this domain name, it is made up of several different parts. These different parts have a hierarchical relationship with each other. One of the last. CN is the first layer of the domain name. COM is the second level of the domain name, and. Ctocio is the real domain name, in the third layer, and so on. At this point we can see that the domain name from the back to the front of the hierarchy is similar to an inverted tree-type structure. One of the first layers. CN is called the geographical top-level domain name. Under these geographical top-level domain names, you can also define secondary domain names as needed. such as the top-level domain in our country. CN also set up a. com,.net,.org,.gov,.edu, as well as China's various administrative divisions of the letter representatives such as. BJ on behalf of Beijing,. Sh for Shanghai and so on. So when visiting the website, only need to enter the domain name () that can open the corresponding Web site, and do not need to enter difficult to remember the IP address.

Oracle database system is a large distributed database system. Sometimes, for performance reasons, it is often necessary to deploy multiple database systems in multiple parts of the enterprise, which constitutes an Oracle distributed network environment. In order to guarantee the uniqueness of each database name, Oracle database system borrows the naming rules of domain name, and uses the domain name structure to name the distributed database. That is, the global name of a database consists of its database name and the domain name of the database. Suppose that now a company in Zhejiang has Ningbo, Hangzhou, Zhoushan three offices, deployed three Oracle databases, including Hangzhou as the headquarters. The structure diagram is as follows:

According to the global database name naming rules, Hangzhou company database name is Oral.dtm Ningbo Company's database name is ORAL.NINGBO.DTM, Zhoushan Company's database name is ORAL.ZHOUZHAN.DTM. At this point, it is very convenient for the application to connect to the databases of different departments. You can specify the data object you want to access through the global database name. With simple modifications, users can connect to the database they need to connect to. Alternatively, you can configure a default domain in the network environment so that you do not need to specify a domain name to Access database objects in the default domain.

The use of global database names can provide two benefits. One is easy to expand the database. If the enterprise is now likely to use only one database to handle the business. But when the size of the enterprise expands, a database may not be able to meet the performance requirements. Or, for reasons such as enterprise consolidation, a distributed database environment needs to be deployed. The database environment can be expanded without the need to change the original existing database. The second is to facilitate the connection of the database. It is convenient to use global database names when a user replaces a different database.

Therefore, the author recommends that the database administrator, even if the enterprise currently has only one Oracle database, it is best to name the global database naming convention can also define its name. To the benefit of the subsequent database expansion, but also facilitate the day-to-day maintenance of the database administrator.