It is worth to remember that each control file is exact copy of primary control file. Multiplexing control files using spfile or pfile multiplexing control file using spfile sql show parameter spfile. The control file must be available for writing by the oracle database server whenever the database is open or up. 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. How to multiplex control files in oracle it blogger tips. The spfile can be thought of as a control file that is used by oracle to store the initialization parameters. 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. Enabling session multiplexing enabling access control.
As alternatively, use the stringwrite command to covert the binary file to text file. Jan 01, 2012 how to multiplex a controlfile, spfile scenario. In this post i like show a simple how to for create several controlfiles cf into an asm. If we have the copy of the control files we can simply copy the control file from the next location. If a control file is lost, a copy of the control file can be used to restart the instance without database recovery. Stack overflow for teams is a private, secure spot for you and your coworkers to find and share information. The spfile is a serverside initialization parameter file. The control file of an oracle database is created at the same time as the database. Jul 25, 2011 spfile server parameter file is a persistent server side binary file. Multiplexing control files to several different file systems decreases the probability of losing control files. Instead it can only be altered using the alter system command. In this post we show how to multiplex the oracle controlfile in asm. Jan 21, 2002 the spfile can be thought of as a control file that is used by oracle to store the initialization parameters. Control files can be multiplexed up to eight times.
In the case of corruption or loss recovery is no more difficult than copying the control file from another location. With shared server, many user processes connect to a dispatcher. The attributes connections, dispatchers, listener, multiplex. If your sid is called testdb, the resulting pfile should be called inittestdb. Total system global area 755769344 bytes fixed size 2217184 bytes variable size 478153504. The control file autobackup filename has a default format of %f for all device types, so that rman can. There are two ways to multiplex the oracle control files, init. See the post multiplexing control files for more information on multiplexing the control file. If you are using a pfile, it takes on the form of initsid. One way to multiplex control files is to store a control file copy on every disk drive that stores members of redo log groups, if the redo log is multiplexed. Hot backup means that the database doesnt have to be down. The oracle server creates and maintains all files listed in this parameter when the instance is started.
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. What is oracle control file and how to do multiplexing. Orneklerle oracle 11g r2 ve genel kavramlar oracle 11g r2 general concepts with examples was published as a book. 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. Records in some sections in the control file are circularly reusable while records in. In order to multiplex move the controlfile to a different diskgroup.
Multiplexing a control file in oracle database is quite simple and mandatory. 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. Stay tuned we will update new oracle dba interview questions with answers frequently. Make physical copies of control file just like copy a file and paste it in another location. Mar 14, 2009 every time a change is made to control file, an auto backup will take place of both control file and spfile.
Multiplexing control files solutions experts exchange. How to multiplex the oracle controlfile in asm performance. Spfile server parameter file is a persistent server side binary file. Rman script for full hot backup including spfile and. 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. How to multiplex redo log files in oracle it blogger tips. Please note that if the control file has been configured to autobackup mode, a backup of the spfile will also be created automatically. Having multiple copies of control files will reduce risk of result of loss of control files. If you are not using oraclemanaged files, then the database creates a control file and uses a default filename. Once a spfile has been created, oracle will use it at the next startup. How to multiplex controlfile in oracle rac or asm it. I have read the sequence of files used during startup, 1 spfile.
Dec 06, 2016 the control file must be available for writing by the oracle database server whenever the database is open or up. Properties, you actually look at the splistitem to which the file is attached and look at its properties from sharepoints content database. Jan 08, 2018 java project tutorial make login and register form step by step using netbeans and mysql database duration. On the next startup, use startup without the pfile parameter and the new spfile will be used. The steps to multiplex control files using an spfile are describe bellow. Jul 08, 2014 in my situation i have unfortunately lost one of control file from two files.
If a control file is damaged due to a disk failure, the associated instance must be shut down. This has not been tested on databases prior to version 11g. Suppose we have two hd and those two are mount as ua1 and ua2. Follow script to use in rman to perform a full hot backup in an oracle database, including its controlfile and spfile. 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. Oracle startup initialization parameters morgans library. Multiplexing control file using spfile oracle tutorialdba. 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. In my situation i have unfortunately lost one of control file from two files. In order to multiplex move the controlfile to a different diskgroup, you can use the following procedure.
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. Dec 25, 2012 oracle recommends multiplexing the control files. At the time of creating the database by dbca we can do multiplexing or we can also do later manually as described below. Database spfile and oracle net configuration file samples. 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. As we know, every oracle database has a control file, which is a small binary file that records the physical structure of the database. Simply log to rman with your database open and run the following dont forget to adjust the paths to your own need. True both in out ticks 0 off no false ticks multiplex. Backup your spfile, and controlfile, it does not cost money. The procedure used to multiplex control files can also be used to move or rename control files. Multiplexing control file in oracle oracle administration.
Jan 11, 2018 in this post i like show a simple how to for create several controlfiles cf into an asm. The oracle spfile is a binary representation of the text0based init. Controlfile contains database name, database creation date, tablespace names, physical location of datafiles and recovery information. The spfile is different from the pfile in that it can not be directly edited. To demonstrate this error, i have intentionally deleted control file i. The oracle server creates and maintains all files listed in this parameter when the instance is. The first step in multiplexing the control files is to see where the exiting control files are located. Unfortunately spfile changes by itself dont constitute an auto backup. Oracle dba interview questions and answers 2020 updated. In addition to auto backups when control file changes, every time you have a backup statement in your rman script ex. Session multiplexing, available with oracle connection manager, enables multiple client sessions. Multiplex control file in 11gr2 rac asm using rman expert.
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. So we need to move at list one controlfile in ua1 and we move the 3rd contronlife. This document provides a step by step guide to add extra control files to a database whose storage is on asm. For standalone database multiplexing controlfile is straight forward, but for rac,we need to follow below steps. Having multiple control files reduces the risk of control file loss due to corruption or accidental removal. Rman oracles recovery manager will backup the spfile with the database control file if setting configure controlfile autobackup is on the. Back up the control file after the database structure changes. How to add control file when using asm oracle database. Jan 10, 2012 follow script to use in rman to perform a full hot backup in an oracle database, including its controlfile and spfile. What happens behind the scene, when you upload a file having some office properties set, is that sharepoint copies them to samenamed fields in splistitem. Copy an existing control file to a new location, using operating system commands.
Controlfile multiplexing using asm lokeshaggarwals dba. How to multiplex control files in oracle project envision. The locations and names of control files is stored. Maintaining the control file my foot steps from programming. Oracle always recommends to keep the controlfile in multiple diskgroups. Oracle dba, multiplex control file, spfile scenario, 1e15.
In this case you are doing the same with the control file. Parameters in pfile can be edited using any text editor. When the oracle database starts, it reads the parameter file called spfile or pfile and learn the location of the control file. In either case, to recover from this problem is simple and does not require going to the last backup provided your control files are multiplexed. Java project tutorial make login and register form step by step using netbeans and mysql database duration.
If high redundancy, oracle say to use 1 control file and log member to reduce the. Every time a change is made to control file, an auto backup will take place of both control file and spfile. This chapter describes how to configure dispatcher. Multiplexing the control file oracle certified professional. Oracle db multiplexing control files watch more videos at. Mar 25, 2015 once a spfile has been created, oracle will use it at the next startup. If you are not using data guard broker, you must also set the parameters in table a6 through table a9. The files marked with should be multiplexed over a minimum of 2 locations. This clause lets you specify a name for the server parameter file you are creating. The database name names and locations of associated datafiles and redo log files. Editing an spfile directly will corrupt the file and the start up of the database or instance will not be possible. Make sure dispatcher and telnet server hostname is as per production requirement.
This file also acts as the brain for our oracle database. Spfile should only be modified through alter system set command. 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. How to multiplex the oracle controlfile in asm performance tuning. Learn more how to check whether oracle instance is started using pfile or spfile.
1523 1505 1425 1465 239 1440 536 1210 1308 1327 1108 41 1321 761 106 702 1113 1 1004 415 570 1331 1330 363 1496 906 1209 1024 659 419 957 1266 1314 1320 553 477 1328 1156 857 722 1119 1175 406