Oracle 10g 一主多备的搭建技巧
在Oracle数据库环境中，一主一备是比较传统的使用方式，在灾难发生的时候，可以灵活的切换主备角色，依然可以保持服务的可访问性
在Oracle数据库环境中，一主一备是比较传统的使用方式，在灾难发生的时候，可以灵活的切换主备角色，依然可以保持服务的可访问性。但是一些核心系统来说还是会有更多的过滤，一主一备似乎还是不够稳妥，如果主备出现问题，如果有另外一个备库还是有可选的余地，这种情况不是不可能发生，正是因为核心业务的需要还是需要保证数据的安全。
很多场景下，一主两备会保持这样的场景，一主一备在同一个区域内，这样在出现问题的时候方便切换，如果区域出现故障，可以保证异地的机房可以顺利承接服务。
比如下面的这种方式是比较传统的一主一备的方式。因为是在10g的环境中，所以备库还是Mount，不能open在线接收数据变更。
在这种结构下，如果根据需要去添加另外一个备库节点，就需要考虑到一些负载的因素。毕竟我们不希望主库有很多的数据文件复制工作，尽管duplicate特性还是比较方便的。
这个时候我们可以只动用备库导出响应的备份数据来。如果这个时候主库出现问题，可以随时终止rman备份，直接切换环境。
[img][/img]
当然利用备库导出rman dump，在另外一个备库来做恢复，如果文件路径等等存在偏差，或者限于dump的大小和磁盘空间，可能会把dump放在不同的路径下，就可以直接设定catalog来恢复。
大体的四个步骤如下面的蓝色方框所示。这个时候主库和备库之间还是没有任何的直接关联，所以从这个地方，也把主库的负载降到了最低。
数据库恢复之后，这就是一个新的备库，我们可以通过dg broker来建立和主库的关联关系。这个时候回在三个节点间进行一些配置信息的同步，过程还是比较快的。
就这样，一主两备的环境就搭建好了。
其实我们还可以这么思考，把switchover的场景和failover都结合起来，如果在switchover出现失败的情况下，我们可以动用第二个备库来做failover.
怎么理解呢，switchover在一些外部因素的作用下还是可能会失败，比如在10g版本中，，我们把备库启动到了read only状态，结果数据变更都会延迟，如果延迟够大，rman配置可能会把一些历史的归档给删除掉，尽管RFS把归档传到了备库，但是MRP还没有开始工作，所以备库中的归档还没有使用到。这个时候主库奔溃，那个read only的备库做switchover就很可能失败。
这个时候我们还是保证另外一个备库在mount状态，我们可以直接做failover
本文永久更新链接地址：
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1385
52
Explain InnoDB Full-Text Search capabilities.
Apr 02, 2025 pm 06:09 PM
InnoDB's full-text search capabilities are very powerful, which can significantly improve database query efficiency and ability to process large amounts of text data. 1) InnoDB implements full-text search through inverted indexing, supporting basic and advanced search queries. 2) Use MATCH and AGAINST keywords to search, support Boolean mode and phrase search. 3) Optimization methods include using word segmentation technology, periodic rebuilding of indexes and adjusting cache size to improve performance and accuracy.
How do you alter a table in MySQL using the ALTER TABLE statement?
Mar 19, 2025 pm 03:51 PM
The article discusses using MySQL's ALTER TABLE statement to modify tables, including adding/dropping columns, renaming tables/columns, and changing column data types.
When might a full table scan be faster than using an index in MySQL?
Apr 09, 2025 am 12:05 AM
Full table scanning may be faster in MySQL than using indexes. Specific cases include: 1) the data volume is small; 2) when the query returns a large amount of data; 3) when the index column is not highly selective; 4) when the complex query. By analyzing query plans, optimizing indexes, avoiding over-index and regularly maintaining tables, you can make the best choices in practical applications.
Can I install mysql on Windows 7
Apr 08, 2025 pm 03:21 PM
Yes, MySQL can be installed on Windows 7, and although Microsoft has stopped supporting Windows 7, MySQL is still compatible with it. However, the following points should be noted during the installation process: Download the MySQL installer for Windows. Select the appropriate version of MySQL (community or enterprise). Select the appropriate installation directory and character set during the installation process. Set the root user password and keep it properly. Connect to the database for testing. Note the compatibility and security issues on Windows 7, and it is recommended to upgrade to a supported operating system.
Difference between clustered index and non-clustered index (secondary index) in InnoDB.
Apr 02, 2025 pm 06:25 PM
The difference between clustered index and non-clustered index is: 1. Clustered index stores data rows in the index structure, which is suitable for querying by primary key and range. 2. The non-clustered index stores index key values and pointers to data rows, and is suitable for non-primary key column queries.
What are some popular MySQL GUI tools (e.g., MySQL Workbench, phpMyAdmin)?
Mar 21, 2025 pm 06:28 PM
Article discusses popular MySQL GUI tools like MySQL Workbench and phpMyAdmin, comparing their features and suitability for beginners and advanced users.[159 characters]
How do you handle large datasets in MySQL?
Mar 21, 2025 pm 12:15 PM
Article discusses strategies for handling large datasets in MySQL, including partitioning, sharding, indexing, and query optimization.
How do you drop a table in MySQL using the DROP TABLE statement?
Mar 19, 2025 pm 03:52 PM
The article discusses dropping tables in MySQL using the DROP TABLE statement, emphasizing precautions and risks. It highlights that the action is irreversible without backups, detailing recovery methods and potential production environment hazards.
