11gR2(11.2) RAC TAF Configuration for Admin and Policy Managed Databases (文档 ID 1312749.1)
In this Document
Purpose |
_afrLoop=1459323732561579&id=1312749.1&displayIndex=10&_afrWindowMode=0&_adf.ctrl-state=foyvm6hmv_144#SCOPE">Scope |
Details |
_afrLoop=1459323732561579&id=1312749.1&displayIndex=10&_afrWindowMode=0&_adf.ctrl-state=foyvm6hmv_144#aref_section31">Concepts & Overview |
_afrLoop=1459323732561579&id=1312749.1&displayIndex=10&_afrWindowMode=0&_adf.ctrl-state=foyvm6hmv_144#aref_section32">Administrator-managed Database |
Basic Method |
Preconnect Method |
Policy-managed Database |
Basic Method |
Applies to:
Oracle Database - Enterprise Edition - Version 11.2.0.1 to 11.2.0.3 [Release 11.2]
Oracle Net Services - Version 11.2.0.1 to 11.2.0.3 [Release 11.2]
Information in this document applies to any platform.
Purpose
This article describes Transparent Application Failover (TAF) and provides configuration details for 11gR2(11.2) cluster database.
Scope
This article is intended for Oracle Cluster Administrators who would like more details about TAF. Basic understanding of Oracle Clusterware Database is assumed.
Details
Concepts & Overview
TAF allows Oracle clients to reconnect to a surviving instance in the event of a failure of the instance to which it is connected. There are two types of TAF available, SESSION and SELECT.
SESSION: Session Failover re-creates the connections and sessions to the surviving instance.
SELECT: In addition to recreating the session, Select Failover also replays the queries that were in progress.
There are two methods in which TAF estabilishes the failover connection, BASIC and PRECONNECT.
BASIC: The second connection is re-established only after the first connection to the instance failed.
PRECONNECT: Two connections are established when the client logs in to the database. A login to database will create two connection at the same time. For this to work, clusterware actually starts two services. One main service and another shadow
service.
TAF can be configured at the Oracle Client side in tnsnames.ora or at the Database Server side using the SRVCTL utility. Configuring it at the server is preferred as it is convenient to put the configuration in one place i.e. on the server. This article covers
the configuration at the server using SRVCTL. TAF configuration is associated with the database service.
1. Create the service with SRVCTL
SRVCTL defines services in OCR which is accessible across nodes. The service configuration details can be viewed with the SRVCTL config service command.
2. Start the Service with SRVCTL
When the service is started with SRVCTL, it actually creates a service in the database. The service name and the configuration details of the service created at the database can be viewed with DBA_SERVICES view. Then the SERVICE_NAMES database parameter is
set, which allows PMON to register this service with the listener. Once the new service is registered, remote client connections can established through the listener.
The clusterware automatically starts/stops and manages the services in the database according to the configuration of the service. Manually setting the SERVICE_NAMES parameter in RAC is not allowed as clusterware manages setting this parameter.
Let's have a look at the srvctl syntax for creating service. Databases in 11gR2 can be Administrator-managed or Policy-managed. Certain options can be used only with certain type of database.
-r "<preferred_list>" [-a "<available_list>"] [-P {BASIC | NONE | PRECONNECT}]
-g <server_pool> [-c {UNIFORM | SINGLETON}]
[-k <net_num>]
[-l [PRIMARY][,PHYSICAL_STANDBY][,LOGICAL_STANDBY][,SNAPSHOT_STANDBY]]
[-y {AUTOMATIC | MANUAL}]
[-q {TRUE|FALSE}]
[-x {TRUE|FALSE}]
[-j {SHORT|LONG}]
[-B {NONE|SERVICE_TIME|THROUGHPUT}]
[-e {NONE|SESSION|SELECT}]
[-m {NONE|BASIC}]
[-z <failover_retries>]
[-w <failover_delay>]
Here is the description of the options that we are going to use in configuring TAF.
-r "<preferred_list>" [-a "<available_list>"] [-P {BASIC | NONE | PRECONNECT}]
This clause is valid only for Administrator-managed database which support PRECONNECT method.
-g <server_pool> [-c {UNIFORM | SINGLETON}]
This clause is valid only for Policy-managed database where in PRECONNECT method is not available.
The above two options instruct clusterware on how to handle this service.
[-e {NONE|SESSION|SELECT}]
This defines the type of TAF whether SESSION or SELECT.
[-m {NONE|BASIC}]
This defines the method of TAF.
[-z <failover_retries>]
This defines the the number of times to attempt to connect after a failover.
[-w <failover_delay>]
This defines the amount of time in seconds to wait between connect attempts.
Above four options are passed to database while starting up the service and is viewable in DBA_SERVICES view.
Administrator-managed Database
Basic Method
1. Create Service
Syntax:
srvctl add service -d <db_unique_name> -s <service_name>
-r "<preferred_list>" [-a "<available_list>"] [-P {BASIC | NONE | PRECONNECT}]
[-e {NONE|SESSION|SELECT}]
[-m {NONE|BASIC}]
[-z <failover_retries>]
[-w <failover_delay>]
Example:
$ srvctl add service -d db112 -s mysrvb
-r db1121,db1122 -P basic -e select -m
basic -z 10 -w 2
2. Start the service
$ srvctl start service -d db112 -s mysrvb
Check if the service is registered with the listener.
. . .
. . .
Service "mysrvb" has 2 instance(s).
Instance "db1121", status READY, has 1 handler(s) for this service...
Instance "db1122", status READY, has 1 handler(s) for this service...
. . .
. . .
3. Make a connection.
The client connect string does not require any special TAF parameters. A simple tnsnames.ora entry as shown below will do.
(description =
(address = (protocol=tcp)(host=secrac-scan)(port=1521))
(connect_data=
(service_name=mysrvb)
)
)
$ sqlplus scott/tiger@mysrvb
Once connected GV$SESSION view will reflect the connection made is TAF enabled. The FAILOVER_METHOD and FAILOVER_TYPE column reflects it and this confirms the TAF configuration is correct.
INST_ID USERNAME SERVICE_NAME FAILOVER_TYPE FAILOVER_M FAI
------- -------- ------------ ------------- ---------- ---
1 SCOTT mysrvb SELECT BASIC NO
Note that this client has connected to the instance 1 with BASIC method and SELECT type.
Preconnect Method
1. Create service
Syntax:
srvctl add service -d <db_unique_name> -s <service_name>
-r "<preferred_list>" [-a "<available_list>"] [-P {BASIC | NONE | PRECONNECT}]
[-e {NONE|SESSION|SELECT}]
[-m {NONE|BASIC}]
Example:
$ srvctl add service -d db112 -s mysrv
-r db1121 -a db1122 -P preconnect
* The -e, -m option should be set to none. Omitting this option actually sets it to none.
* Use both -r and -a option for preconnect so that a shadow service will be started.
2. Start the service.
$ srvctl start service -d db112 -s mysrv
Preconnect creates an additional shadow service.
. . .
. . .
ora.db112.mysrv.svc
1 ONLINE ONLINE secrac1
ora.db112.mysrv_preconnect.svc
1 ONLINE ONLINE secrac3
. . .
. . .
Note that the service 'mysrv' is started on the preferred instance. And the shadow service
'mysrv_preconnect' is started on the available instance. The shadow service is always defined as
<servicename>_preconnect.
Check if the service is correctly registered with the listener.
. . .
. . .
Service "mysrv" has 1 instance(s).
Instance "db1121", status READY, has 1 handler(s) for this service...
Service "mysrv_preconnect" has 1 instance(s).
Instance "db1122", status READY, has 1 handler(s) for this service...
. . .
. . .
3. Define TNS entry.
Preconnect requires special parameters at the client side tnsnames.ora file. The TAF Type and the TAF method is actually specified at the client end.
(description =
(address = (protocol=tcp)(host=secrac-scan)(port=1521))
(connect_data=
(service_name=mysrv)
(failover_mode=
(backup=mysrv_preconnect)
(type=select)
(method=preconnect)
)
)
)
mysrv_preconnect =
(description =
(address = (protocol=tcp)(host=secrac-scan)(port=1521))
(connect_data=(service_name=mysrv_preconnect))
)
Connect to the database with this tns entry
$sqlplus scott/tiger@mysrv
INST_ID USERNAME SERVICE_NAME FAILOVER_TYPE FAILOVER_M FAI
------- -------- ---------------- ------------- ---------- ---
1 SCOTT mysrv SELECT PRECONNECT NO
2 SCOTT mysrv_preconnect NONE NONE NO
Note that the client has made two connections. The first one is the active main connection with PRECONNECT method and SELECT type. The second one is the shadow connection that will be used if the connection to the first instance fails.
Policy-managed Database
Basic Method
1. Create the service
Syntax:
srvctl add service -d <db_unique_name> -s <service_name>
-g <server_pool> [-c {UNIFORM | SINGLETON}]
[-e {NONE|SESSION|SELECT}]
[-m {NONE|BASIC}]
[-z <failover_retries>]
[-w <failover_delay>]
Example:
$ srvctl add service -d db1 -s mysrvp
-g mysrvpool -c uniform -e select -m basic
-z 10 -w 2
2. Start the service
$ srvctl start service -d db1 -s mysrvp
Check if the service is correctly registered with the listener
. . .
. . .
Service "mysrvp" has 2 instance(s).
Instance "db1_1", status READY, has 1 handler(s) for this service...
Instance "db1_2", status READY, has 1 handler(s) for this service...
. . .
. . .
3. Make a connection.
The client connect string does not require any special TAF parameters. A simple tnsnames.ora entry as shown below will do.
(description =
(address = (protocol=tcp)(host=secrac-scan)(port=1521))
(connect_data=
(service_name=mysrvp)
)
)
$ sqlplus scott/tiger@mysrvp
INST_ID USERNAME SERVICE_NAME FAILOVER_TYPE FAILOVER_M FAI
------- -------- ------------ ------------- ---------- ---
1 SCOTT mysrvp SELECT BASIC NO
11gR2(11.2) RAC TAF Configuration for Admin and Policy Managed Databases (文档 ID 1312749.1)的更多相关文章
- 11gR2 Database Services for "Policy" and "Administrator" Managed Databases (文档 ID 1481647.1)
In this Document Purpose _afrLoop=1459311711568804&id=1481647.1&displayIndex=6&_afrW ...
- Best Practices and Recommendations for RAC databases with SGA size over 100GB (文档 ID 1619155.1)
Best Practices and Recommendations for RAC databases with SGA size over 100GB (文档 ID 1619155.1) APPL ...
- Troubleshooting 10g and 11.1 Clusterware Reboots (文档 ID 265769.1)
Troubleshooting 10g and 11.1 Clusterware Reboots (文档 ID 265769.1) This document is intended for DBA' ...
- Clusterware 和 RAC 中的域名解析的配置校验和检查 (文档 ID 1945838.1)
适用于: Oracle Database - Enterprise Edition - 版本 10.1.0.2 到 12.1.0.1 [发行版 10.1 到 12.1]Oracle Database ...
- 如何诊断 11.2 集群节点驱逐问题 (文档 ID 1674872.1)
适用于: Oracle Database - Enterprise Edition - 版本 11.2.0.1 到 11.2.0.2 [发行版 11.2]本文档所含信息适用于所有平台 用途 这篇文档提 ...
- How to remove a Data Guard Configuration from Primary Database (文档 ID 733794.1)
APPLIES TO: Oracle Database - Enterprise Edition - Version 10.1.0.2 to 11.2.0.3 [Release 10.1 to 11. ...
- Security Configuration and Auditing Scripts for Oracle E-Business Suite (文档 ID 2069190.1)
This document provides the security configuration and auditing scripts for Oracle E-Business Suite. ...
- 跟我学SharePoint 2013视频培训课程——删除恢复、文档离线工作(11)
课程简介 第11天,怎样在SharePoint 2013中删除.恢复文档.文档离线工作. 视频 SharePoint 2013 交流群 41032413
- 【总文档】rac增加新节点的方法步骤 How to Add Node/Instance or Remove Node/Instance in 10gR2, 11gR1, 11gR2 and 12c Oracle Clusterware and RAC
[总文档]How to Add Node/Instance or Remove Node/Instance in 10gR2, 11gR1, 11gR2 and 12c Oracle Clusterw ...
随机推荐
- js中with、this的用法
with 语句 为一个或一组语句指定默认对象. 用法:with (<对象>) <语句>; with 语句通常用来缩短特定情形下必须写的代码量.在下面的例子中,请注意 Math ...
- mysql如何开启远程连接
链接地址:http://jingyan.baidu.com/article/046a7b3ed85f3ef9c27fa9dc.html 大家在公司工作中,经常会遇到mysql数据库存储于某个人的电脑上 ...
- 一个开发原则:永远不要返回NULL
看一篇文章:10个经典的java开发原则,里面一个原则:永远不要返回NULL. 说实在的,我对这个原则体会不是很深,平时在使用对象前,检查是否为null已经成了习惯,也是我要求开发人员的一个标准动作. ...
- UISearchBar控件
摘自:http://blog.sina.com.cn/s/blog_7b9d64af0101dfg8.html UISearchBar控件就是要为你完成搜索功能的一个专用控件.它集成了很多你意想不到的 ...
- new Handler().postDelayed() 延迟intent跳转
原文地址http://blog.csdn.net/x605940745/article/details/19401549 new Handler().postDelayed(new Runnable( ...
- log4net使用流程
前面大致介绍了一下log4net的概述和结构.既然都清楚了,下面我来介绍一下如何使用log4net. 使用流程 1.这里所说的使用流程就是使用log4net.dll,首先要根据你的平台来找出对应的版本 ...
- Android 讲述Help提示框
Android 讲述Help提示框 XML/HTML代码 <stringname="help_dialog_text"> <i>Author:fonter. ...
- 【BOI2007】【BZOJ1176】Mokia
1176: [Balkan2007]Mokia Time Limit: 30 Sec Memory Limit: 162 MB Submit: 1059 Solved: 432 [Submit][St ...
- EasyUI - 后台管理系统 - 登陆模块
效果: --- --- Html代码: <div id="login"> <p>账户:<input type="text" id= ...
- linux脚本:shell, 判断输入参数的个数(命令行)
if [ $# != 3 ] ; thenecho "USAGE: $0 from to"echo " e.g.: $0 ~/oucaijun/from ~/oucaij ...