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Mouhamadou Diaw

Mouhamadou Diaw

Configure Data Guard between 2 DB Systems with Oracle 21c

By | Database Administration & Monitoring, Database management, Operation systems, Oracle | No Comments

In this previous blog, I have configured 2 DB systems with Oracle 21c in an ODA 19.14. Now let’s continue and show how we can configure a Data Guard between these 2 servers. One option is to manually create the Data Guard as we do in a non-ODA environment. The second option that I am showing is to use the odacli command to configure the Data Guard. All steps are described in Oracle documentation The…

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Mouhamadou Diaw

Configure DB System Oracle 21c in a ODA 19.14

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

One question we may ask is that if it is possible to deploy an Oracle 21c database in an ODA as the latest version for ODA is actually 19.x The answer is Yes. Since ODA release 19.12, we can install a DB system with Oracle 21c while the bare metal system runs Oracle Grid Infrastructure 19.x. To see the supported versions on the DB system just run the command describe-dbsystem-image [[email protected] ~]# odacli describe-dbsystem-image DB…

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Mouhamadou Diaw

Oracle Data Guard : Where to Host The Master Observer

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

An observer is an OCI client that connects to the primary and target standby databases using the same SYS credentials you used when you connected to the Oracle Data Guard configuration with DGMGRL. The observer is highly recommended in a Data Guard environment. But it is mandatory if a Fast-Start Failover is configured. Since Oracle 12.2 we can have up to 3 observers and the maximum number of observers is increased to 4 since Oracle…

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Mouhamadou Diaw

Oracle 21c : Dealing with FastStartFailoverActionOnPreCalloutFailure

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

In a previous blog I talked about the FSFO callout scripts which is a new feature with Oracle 21c with the broker. This feature will allow to execute some tasks before and after a fast-start failover. By default, the automatic failover will not happen if the pre-script fails. Maybe it’s not what we want, sometimes we will want to continue the automatic failover even if the pre-tasks did not execute successfully. Oracle has a parameter…

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Mouhamadou Diaw

Active Duplicate from standby database

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

Generally we do active duplicate from primary database, but I think it should be fine to see what happen if we do active duplicate a database from a standby database. So, I do some tests and I write the results in this blog Below the actual configuration of my Data Guard environment DGMGRL> show configuration Configuration – db21 Protection Mode: MaxPerformance Members: DB21_SITE1 – Primary database DB21_SITE2 – Physical standby database Fast-Start Failover: Disabled Configuration…

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Mouhamadou Diaw

Oracle 21c Broker : Fast-Start Failover Callout Scripts in Action

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

With Oracle 21c (In fact Oracle 20c), we have a nice new feature with the broker which is the Fast-start Failover Callout Configuration scripts. I talked about this feature in some presentations I did about the new features with Oracle 21c for the broker This feature will allow to automate tasks that must be performed before and after a fast-start failover operation. Yes this means that with Oracle 21c, we can configure some tasks to…

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Mouhamadou Diaw

PDB Snapshot Carousel with Oracle 21c

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

In a previous blog , I talked about refreshable PDB technology which can be used to refresh a target PDB. We have seen here how the target refreshable PDB can be used as a master to provide PDB snapshots. In this blog we are going to continue in the same topic and talk about PDB Snapshot Carousel which is a library of PDB snaphots. It consists to automatically or manually generate a certain number of…

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Mouhamadou Diaw

Pluggable Database Snapshots with Oracle 21c

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

In a previous blog , I talked about refreshable PDB technology which can be used to refresh a target PDB. The target PDB can be in mounted state (mandatory to be refreshed) or can be opened in a read only mode. One application is to use the target refreshable PDB as a master to provide PDB snapshots. A PDB snapshot is copy of a PDB at a given time. The source PDB can be open…

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Mouhamadou Diaw

Managing Refreshable Clone Pluggable Databases with Oracle 21c

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

A refreshable clone PDB is a way to refresh a single PDB instead of refreshing all PDBs in a container as in a Data Guard environment. It consists to make a clone of a source PDB and the clone PDB is updated with redo accumulated since the last redo log apply In this blog I did some tests of this feature Refreshable pluggable databases. I am doing my test with Oracle 21c but this feature…

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Mouhamadou Diaw

Character Sets and Oracle 21c PDBs : How It Works

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

When creating a database in a multitenant environment we must understand how character set works for CDB and PDBS. In Oracle documentation we can find following lines -When the character set of the CDB root is AL32UTF8, PDBs that are plugged into the CDB can have a different character set from the CDB root. PDBs that you create from PDB$SEED inherit the AL32UTF8 character set from it, but you can migrate the PDB to a…

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