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Data Guard

Active Data Guard services in Multitenant

By Franck Pachot . A database (or the CDB in multitenant) registers its name as the default service. When a standby database is on the same server, or same cluster, you have no problem because this database name is the db_unique_name which is different between the primary and the standby(s). In multitenant, in addition to that, each PDB registers its… 

When PDB name conflicts with CDB name

By Franck Pachot . Going to multitenant architecture is not a big change. The administration things (DBA, monitoring, backups) connect to the CDB and the application things connect to the PDB. Without the multitenant option, it is still recommended to go to the CDB architecture. The non-CDB is deprecated and the multitenant architecture brings interesting features. People often ask how… 

ODA X6 2S 2M 2L HA: Small Medium Large and High Availability

By Franck Pachot . There are 4 models of Oracle Database Appliance with the new ODA X6 which is for the moment the latest ODA hardware version. One is similar to the previous X5-2 one, and 3 smaller ones known as ODA Lite. They are 1 year old already, here is a small recap of the differences and links to… 

Display Data Guard configuration in SQL Developer

By Franck Pachot . The latest version of SQL Developer, the 17.2 one released after Q2 of 2017, has a new item in the DBA view showing the Data Guard configuration. This is the occasion to show how you can cascade the log shipping in Oracle 12c A quick note about this new versioning: this is the release for 2017… 

12c NSSn process for Data Guard SYNC transport

By Franck Pachot . In a previous post https://www.dbi-services.com/blog/dataguard-wait-events-have-changed-in-12c/ I mentioned the new processes NSA for ASYNC transport and NSS for SYNC transport. I’m answering a bit late to a comment about the number of processes: yes there is one NSSn process per LOG_ARCHIVE_DEST_n destination in SYNC and the numbers match. Here is my configuration with two physical standby: DGMGRL>… 

12c nologging and Data Guard

By Franck Pachot . The title sounds weird because Data Guard synchronisation is based on the redo stream, so it makes no sense to do nologging operations on the primary. And this is the reason why we set FORCE LOGGING on a Data Guard configuration. However, to lower the downtime of a migration done with Data Pump, you may want… 

Listener and Virtual IP

By Franck Pachot . When you configure a standby database, you want the application to transparently connect to the primary database, wherever it is. That’s the role of Transparent Application Failover, but this requires configuration on the client side. If you can’t configure TAF, you can use a virtual IP address. But then the question is how to configure the… 

How many members for standby redo logs?

By Franck Pachot . I see lot of databases with two members for redo logs and also two members for standby redo logs. Why not, but when asking I realized that there are some mis-comprehension about it. And what was recommended 10 years ago may be different today. Online and Stanbdy redo logs Your transactions happen on the primary database… 

Oracle 12cR2, RAC, Cloud, ACFS, PDB thin clones and asmadmin

By Franck Pachot . In the Oracle Public Cloud, fast provisioning gets all its meaning when creating a RAC database service: in one hour you can get an operational highly available multitenant database. You can even create it in Data Guard for Disaster Recovery. Now, Oracle is pushing ACFS to store the datafiles rather than direct ASM. Especially in multitenant… 

Oracle 12c – How to Recover lost DataGuard Broker Configuration Files

By William Sescu If you are using RMAN to back up your database, you are already doing the right thing. However, RMAN does not take care of everything. e.g. it is not backing up the following things, to mention just a few. Oracle Home Grid Infrastructure Home Data Guard broker files Password File SQL*Net file like ldap.ora, sqlnet.ora, tnsnames.ora and… 

12cR2: Recover nonlogged blocks after NOLOGGING in Data Guard

By Franck Pachot . You can accept to do NOLOGGING operations on bulk loads or index build according that you do a backup just after, and that your recovery plan mentions how to load the data again in case of media recovery. With a standby database, we usually force logging because we want redo to be generated for all operations… 

12cR2 DBCA can create a standby database

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…