Home IT Linux Windows Database Network Programming Server Mobile  
           
  Home \ Database \ Oracle TAF Analysis     - Linux development environment to build and use the directory structure and file --Linux (Linux)

- Overall Physical Migration of Oracle Database with (Database)

- Linux in order to make NMAP hide and seek with the firewall (Linux)

- init level settings for Linux / etc / inittab file into six (restart) or does not support the level of solution (Linux)

- CentOS 7 How to connect to a wireless network (Linux)

- Performance comparison Fibonacci recursive and non-recursive (Programming)

- How to compare PDF files on Ubuntu (Linux)

- GitHub multiplayer co-development configuration (Linux)

- The first IOS Objective-C program (Programming)

- Installation Elementary OS Freya to do some settings (Linux)

- AngularJS (Programming)

- Oracle local user login authentication fails ORA-01031 insufficient privileges (Database)

- Oracle view object space usage show_space (Database)

- MongoDB Learning the notes (Database)

- Linux fast set ip bond (Linux)

- Ubuntu 14.04 next upgrade to GNOME 3.12 (Linux)

- Linux nice program origin of the name (Linux)

- CentOS 5.5 install ntop (Linux)

- How to test your MongoDB application upgrade? (Database)

- Analysis of common mistakes when compiling MySQL installation (Database)

 
         
  Oracle TAF Analysis
     
  Add Date : 2018-11-21      
         
       
         
  Using rac time, there are several very shiny use properties, is a load balance, this is no doubt, has really done a lot of improvement, load balance multiple vip addresses from Oracle 10g version of the beginning, to 11g version further load balance improved scan-ip, it has really done a great simplification.

In failover implementation, there are still some limited use, such as 11g default scan-ip default implementation of it is still no failover option, if two nodes linked to a node, then the original connection to continue query will prompt session has been disconnected, you need to reconnect.

Many applications are so used scan-ip, also we are at peace, so for failover option or a certain choice, if the failover implementation, in simple terms, mainly through the exchange of time or resources to achieve the exchange.

How to understand it.

We assume that there are two nodes, if a session is connected to the node 2, node 2 abruptly hung up, then there is a way through a failover for time or exchange resources.

For example, for time, in order to achieve faster speeds failover, failover method has preconnect, such pre-connection will still take up more resources, or will pre-empt some additional resources on each node, when switching relatively smoother, faster. This is the way preconect

Another case, in the event of a failover situation, go to the corresponding switching resources, there will be some intermediate Caton, but resources are relatively much smaller. This is the default basic mode.

failover method for the user to focus on when to create a connection to an instance, the basic approach will be taken to judge when a fault occurs, there is a delay of taste, preconnect is a rainy day, after the first ready, in the event of failure, faster switching from the actual applications, or basic in this way more versatile.

For failover type is, rac implementation richer and flexible, this is really unthinkable in other databases. This time it is that the particle size for the user to control the implementation of sql.

For example, we have a lot of queries on node 2, node 2 abruptly hung up the results, then this time, there are two types of failover, that the query is being executed, for example, there are 10,000 data, just when the results of failure detected 8000, then the remaining 2000 how to deal with.

One way is to use select, that is, failover completes, continue to record the rest of the 2000 return, of course, there will be some intermediate context switching for users or substantially transparent, but there will be some delay.

Another direct disconnected asked to re-query. This type is session

Vip by means of configuration to achieve load balance in the 10g version + failover configuration is as follows:

racdb =
(DESCRIPTION =

  (ADDRESS = (PROTOCOL = TCP) (HOST = 192.168.3.101) (PORT = 1521))

  (ADDRESS = (PROTOCOL = TCP) (HOST = 192.168.3.201) (PORT = 1521))

  (LOAD_BALANCE = yes)

  (FAILOVER = ON)

  (CONNECT_DATA =

    (SERVER = DEDICATED)

    (SERVICE_NAME = racdb)

    (FAILOVER_MODE =

      (TYPE = SELECT)

      (METHOD = BASIC)

      (RETRIES = 30)

      (DELAY = 5))))

11g of scan-ip If you also want to extend failover, also need to set failover_mode and the corresponding type.

Of course there is a difference is in 10g we can to complete the configuration by dbca, is simple and clear.
 In 11g, only by means of a command or EM to achieve. I do not know why this part of the graphical interface functions to get rid of.
 In fact, the command is not too much trouble, we can use the following way to do a simple configuration.
 For example, we have chosen to taf basic failover_mode created for racdb_taf

srvctl add service -d RACDB -s racdb_taf -r "RACDB1, RACDB2" -P BASIC
 bash-4.1 $ crs_stat -t | grep taf
 Name Type Target State Host
 -------------------------------------------------- ----------
 ora .... taf.svc ora .... ce.type OFFLINE OFFLINE
We open hand
srvctl start service -d RACDB -s racdb_taf
     

Then to configure more properties by dbms_service.
execute dbms_service.modify_service (service_name => 'racdb_taf', aq_ha_notifications => true, failover_method => dbms_service.failover_method_basic, failover_type => dbms_service.failover_type_select, failover_retries => 181, failover_delay => 5, clb_goal => dbms_service.clb_goal_long);

In the database you can easily view the service conditions.
SQL> select service_id, name from dba_services;

SERVICE_ID NAME
 ---------- ---------------------------------------- ------------------------
  1 SYS $ BACKGROUND
  2 SYS $ USERS
  3 racdb_taf
  5 RACDBXDB
  6 RACDB
 select name, failover_method, failover_type, failover_retries, goal, clb_goal, aq_ha_notifications from dba_services where service_id = 3;
     
         
       
         
  More:      
 
- Implement binary search algorithm in C language (Programming)
- Linux Network Programming - signal blocking and shielding (block, unblock) (Programming)
- Install Debian Linux with R on the Android system (Linux)
- Python implementation restart the router (Programming)
- Oracle 12c users create (Database)
- Process safety monitoring and protection under the Linux operating system (Linux)
- To install and deploy Java applications under CentOS 6.5 (Linux)
- FileZilla FTP && TLS connection settings of (Linux)
- Oracle 12c R2 new feature dbca command to create a standby database (Database)
- Fedora 22 users to install the VLC media player (Linux)
- Nginx request processing (Server)
- History and Statistics tuptime use tools to view Linux server system boot time (Server)
- Grub2: Save Your bootloader (Linux)
- RHEL5 establish a local yum source (Linux)
- NAT and firewall under Linux (Linux)
- Android Notification (Programming)
- Without Visual Studio .NET Windows application development (Programming)
- Ubuntu 14.04 How to set up an SSH without password (Linux)
- The Rabbitmq installation under CentOS 6.4 (Linux)
- Three strategies to teach you to release the device memory (Linux)
     
           
     
  CopyRight 2002-2016 newfreesoft.com, All Rights Reserved.