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Oracle Team

12cR2 DBCA can create a standby database

By | Database Administration & Monitoring | No Comments

By Franck Pachot . Do you like DBCA to create a database from command line, with -silent -createDatabase? On a simple command line you can provision a database, with oratab, tnsnames.ora directory creation and any setting you want. And you can even call a custom script to customize further. But if you want to put it in Data Guard, you have to do the duplicate manually with RMAN. This evolves in 12.2 with a new…

 
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Oracle Team

Oracle 12c – How to Prevent License Violation with Active Data Guard

By | Oracle | No Comments

By William Sescu There are some articles floating around how to prevent a license violation with Active Data Guard. Some of them related to an underscore parameter “_query_on_physical” and some of them related to a startup trigger. Both of them have advantages and disadvantages. E.g. regarding the “_query_on_physical” I can’t find any MOS Note about it, and I don’t know the side effects. Oracle gives us a hard time to disable features that we don’t…

 
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Mouhamadou Diaw

Dataguard Oracle 12.2 : Support for Multiple Observers

By | Database Administration & Monitoring | One Comment

With Oracle 12cR2 it is now possible to configure multiple observers within a single Oracle Data Guard broker configuration. Multiple observers provide an immediate benefit for High Availability. If one observer fails, there are additional observers that can continue to monitor the status of the configuration. In this blog we are going to talk about this new feature. Our configuration have 3 servers: primaserver.localdomain with db_unique_name ORCL_SITE standserver1.localdomain with db_unique_name ORCL_SITE1 standserver2.localdomain with db_unique_name ORCL_SITE2…

 
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Oracle Team

Oracle 12cR2 – DataGuard Switchover with Oracle Wallets

By | Database Administration & Monitoring, Database management | No Comments

By William Sescu I would like to make my DataGuard environment more secure, by eliminating the typing of “connect sys/Manager1″ for my DGMGRL commands. Especially the ones, that I have in my scripts. For example: oracle@dbidg01:/home/oracle/ [DBIT122] dgmgrl <<-EOF > connect sys/Manager1 > show configuration verbose; > EOF or something like that: oracle@dbidg01:/u01/app/oracle/local/dg/ [DBIT122] cat show_config.dg connect sys/Manager1; show configuration; oracle@dbidg01:/u01/app/oracle/local/dg/ [DBIT122] dgmgrl @show_config.dg DGMGRL for Linux: Release 12.2.0.1.0 – Production on Wed Jan 4…

 
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Oracle Team

DB_FLASHBACK_RETENTION_TARGET may hang your database

By | Database Administration & Monitoring | 3 Comments

By Franck Pachot . DB_FLASHBACK_RETENTION_TARGET is set to keep enough flashback logs to be able to flashback database within the specified retention window. But it’s supposed to be a target only, meaning that on space pressure some files can be deleted. But be careful, there are cases where they are not and then the database hangs until you set a lower retention.  

 
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Oracle Team

SYS password on Oracle Cloud Service managed database

By | Database Administration & Monitoring | 2 Comments

By Franck Pachot . When you create a DBaaS on the Oracle Cloud services you have to provide an administration password in the database configuration form. You do not need a password to connect to the VM. You use SSH key for it: on creation you provide the public key that will allow you to connect as the oracle user or the opc user (which can ‘sudo su’). But for the database you need to…

 
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Oracle Team

OCM 12c preparation: Data Guard with OEM

By | Database Administration & Monitoring | One Comment

By Franck Pachot . I never create a Data Guard configuration from Enterprise Manager. It’s not that I don’t like GUI, but it is a lot easier to document it when doing from command line: copy paste the commands (actually I write the commands in the documentation and then copy to execute them so that I’m sure about the documentation). But for OCM 12c preparation, I want to be sure I can do it from…

 
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Oracle Team

SQL> alter database switchover to …

By | Database Administration & Monitoring, Oracle | One Comment

By Franck Pachot . In 12c the manual switchover to physical standby requires only one command (ALTER DATABASE SWITCHOVER) instead of two (ALTER DATABASE COMMIT TO SWITCHOVER on each database). We usually recommend to use the broker and I wanted to see if the broker uses that new command or not. Let’s compare the alert.log for both manual and broker switchover. One simple command I have the broker configured, but try a manual switchover with…

 
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Oracle Team

set state=apply-off and datafile consistency

By | Database Administration & Monitoring, Oracle | One Comment

By Franck Pachot . In a standby database (or in any database you recover) do you think the recovery uses buffer cache? And when you stop the apply in a standby database, do you think the datafiles are in a consistent state? We know the answer, but want to prove it. This is the kind of question you may have, as I did last Friday morning in the train with Ludovico Caldara when going to…

 
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