Records in some sections in the control file are circularly reusable while records in. Control files can be multiplexed up to eight times. So we need to move at list one controlfile in ua1 and we move the 3rd contronlife. Dec 25, 2012 oracle recommends multiplexing the control files. This document provides a step by step guide to add extra control files to a database whose storage is on asm. Jan 21, 2002 the spfile can be thought of as a control file that is used by oracle to store the initialization parameters. Controlfile multiplexing using asm lokeshaggarwals dba. How to multiplex redo log files in oracle posted by anil verma on november 5, 20 all posts, database, how tos, oracle dba no comments as a dba, its your responsibility to multiplex redo log files just like multiplexing control files to protect your organization data loss due to media failure or redo log file corruption. The control file autobackup filename has a default format of %f for all device types, so that rman can. As alternatively, use the stringwrite command to covert the binary file to text file.
If a control file is lost, a copy of the control file can be used to restart the instance without database recovery. In order to multiplex move the controlfile to a different diskgroup. Controlfile contains database name, database creation date, tablespace names, physical location of datafiles and recovery information. To safeguard against a single point of failure of the control file, it is strongly recommended that we have to multiplex the control file, storing each copy on a different physical disk. How to multiplex control files in oracle project envision.
How to add control file when using asm oracle database. Multiplex control file in 11gr2 rac asm using rman expert. I have read the sequence of files used during startup, 1 spfile. What is oracle control file and how to do multiplexing. Aug 16, 2012 if a control file is lost, a copy of the control file can be used to restart the instance without database recovery.
See the post multiplexing control files for more information on multiplexing the control file. Jul 25, 2011 spfile server parameter file is a persistent server side binary file. The oracle spfile is a binary representation of the text0based init. Jan 01, 2012 how to multiplex a controlfile, spfile scenario. If we have the copy of the control files we can simply copy the control file from the next location. Total system global area 755769344 bytes fixed size 2217184 bytes variable size 478153504. Properties, you actually look at the splistitem to which the file is attached and look at its properties from sharepoints content database. Because without the control file, the database cannot be mounted and recovery is so difficult. How to check whether oracle instance is started using pfile. Multiplexing control files solutions experts exchange. Multiplexing control file in oracle oracle administration. Spfile server parameter file is a persistent server side binary file.
The control file of an oracle database is created at the same time as the database. At the time of creating the database by dbca we can do multiplexing or we can also do later manually as described below. Unfortunately spfile changes by itself dont constitute an auto backup. Multiplexing control files using spfile or pfile multiplexing control file using spfile sql show parameter spfile.
Please note that if the control file has been configured to autobackup mode, a backup of the spfile will also be created automatically. Jul 08, 2014 in my situation i have unfortunately lost one of control file from two files. When the oracle database starts, it reads the parameter file called spfile or pfile and learn the location of the control file. With shared server, many user processes connect to a dispatcher. If your sid is called testdb, the resulting pfile should be called inittestdb. The shared server architecture enables a database server to allow many user processes to share very few server processes, so the number of users that can be supported is increased. Jan 11, 2018 in this post i like show a simple how to for create several controlfiles cf into an asm. How to multiplex control files in oracle it blogger tips. Oracle dba, multiplex control file, spfile scenario, 1e15. Parameters in pfile can be edited using any text editor.
Hot backup means that the database doesnt have to be down. Oracle startup initialization parameters morgans library. Mar 22, 2012 multiplex control file 11g rac r2 with asm 22 mar i have created a rac database with 11g r2 and after the creation of the database, we wanted to enable multiplexing for the control files. In this post we show how to multiplex the oracle controlfile in asm. Once the disk drive is repaired, the damaged control file can be restored using the intact copy of the control file from the other disk and the instance can be restarted. True both in out ticks 0 off no false ticks multiplex. How to multiplex the oracle controlfile in asm performance. Enabling session multiplexing enabling access control.
It is worth to remember that each control file is exact copy of primary control file. Rman oracles recovery manager will backup the spfile with the database control file if setting configure controlfile autobackup is on the. Make physical copies of control file just like copy a file and paste it in another location. This has not been tested on databases prior to version 11g. The steps to multiplex control files using an spfile are describe bellow. Instead it can only be altered using the alter system command. The oracle server creates and maintains all files listed in this parameter when the instance is started. Once a spfile has been created, oracle will use it at the next startup. The oracle server creates and maintains all files listed in this parameter when the instance is. The attributes connections, dispatchers, listener, multiplex. The control file must be available for writing by the oracle database server whenever the database is open or up. As we know, every oracle database has a control file, which is a small binary file that records the physical structure of the database. Having multiple copies of control files will reduce risk of result of loss of control files. The database name names and locations of associated datafiles and redo log files.
If control file autobackups are off and the backup includes datafile 1, then rman includes the current control file and spfile in the same backup set as the datafiles. Backup your spfile, and controlfile, it does not cost money. On the next startup, use startup without the pfile parameter and the new spfile will be used. How to multiplex controlfile in oracle rac or asm it.
Multiplexing a control file in oracle database is quite simple and mandatory. Session multiplexing, available with oracle connection manager, enables multiple client sessions. Rman script for full hot backup including spfile and. In this case you are doing the same with the control file. Follow script to use in rman to perform a full hot backup in an oracle database, including its controlfile and spfile. In the case of corruption or loss recovery is no more difficult than copying the control file from another location. If high redundancy, oracle say to use 1 control file and log member to reduce the. Nov 05, 20 how to multiplex redo log files in oracle posted by anil verma on november 5, 20 all posts, database, how tos, oracle dba no comments as a dba, its your responsibility to multiplex redo log files just like multiplexing control files to protect your organization data loss due to media failure or redo log file corruption. Copy an existing control file to a new location, using operating system commands. The spfile can be thought of as a control file that is used by oracle to store the initialization parameters. Orneklerle oracle 11g r2 ve genel kavramlar oracle 11g r2 general concepts with examples was published as a book. Editing an spfile directly will corrupt the file and the start up of the database or instance will not be possible.
If a control file is damaged due to a disk failure, the associated instance must be shut down. Jan 10, 2012 follow script to use in rman to perform a full hot backup in an oracle database, including its controlfile and spfile. Database spfile and oracle net configuration file samples. This file also acts as the brain for our oracle database. If you are using oraclemanaged files, then the initialization parameters you set to enable that feature determine the name and location of the control files, as described in chapter 15. Dec 06, 2016 the control file must be available for writing by the oracle database server whenever the database is open or up. By default, a new oracle database will be working on a pfile, so the spfile must be created from the pfile at the sql prompt.
This chapter describes how to configure dispatcher. Mar 25, 2015 once a spfile has been created, oracle will use it at the next startup. Mar 14, 2009 every time a change is made to control file, an auto backup will take place of both control file and spfile. Table a5 shows data guard best practice spfile parameters for primary, physical standby, and logical standby databases if you are not using data guard broker to manage your database environment. Spfile should only be modified through alter system set command. In this post i like show a simple how to for create several controlfiles cf into an asm. How to multiplex the oracle controlfile in asm performance tuning. Every time a change is made to control file, an auto backup will take place of both control file and spfile. If you are not using oraclemanaged files, then the database creates a control file and uses a default filename. If you are using a pfile, it takes on the form of initsid. Suppose we have two hd and those two are mount as ua1 and ua2.
The files marked with should be multiplexed over a minimum of 2 locations. Learn more how to check whether oracle instance is started using pfile or spfile. Oracle db multiplexing control files watch more videos at. The spfile is a serverside initialization parameter file. The locations and names of control files is stored. Stack overflow for teams is a private, secure spot for you and your coworkers to find and share information. There are two ways to multiplex the oracle control files, init. Stay tuned we will update new oracle dba interview questions with answers frequently. The procedure used to multiplex control files can also be used to move or rename control files.
Make sure dispatcher and telnet server hostname is as per production requirement. Multiplexing the control file oracle certified professional. Java project tutorial make login and register form step by step using netbeans and mysql database duration. How to multiplex redo log files in oracle it blogger tips. Oracle always recommends to keep the controlfile in multiple diskgroups. In my situation i have unfortunately lost one of control file from two files. Multiplexing control file using spfile oracle tutorialdba. Oracle dba interview questions and answers 2020 updated.
Multiplexing control files to several different file systems decreases the probability of losing control files. Back up the control file after the database structure changes. Jan 08, 2018 java project tutorial make login and register form step by step using netbeans and mysql database duration. Simply log to rman with your database open and run the following dont forget to adjust the paths to your own need. To demonstrate this error, i have intentionally deleted control file i. This clause lets you specify a name for the server parameter file you are creating.
1501 1484 429 405 1267 1318 1456 691 1254 913 1466 274 1117 733 709 1377 340 324 943 1507 728 1448 1111 409 1188 1155 644 1463 1020 473 161 1500 460 367 1529 699 962 183 467 614 468 861 253 726 744 1488