What is Data Guard switchover?
What is Data Guard switchover?
Data Guard helps you change the role of a database using either a switchover or a failover: A switchover is a role reversal between the primary database and one of its standby databases. A switchover guarantees no data loss. This is typically done for planned maintenance of the primary system.
What are the services in Data Guard?
Data Guard provides a comprehensive set of services that create, maintain, manage, and monitor one or more standby databases to enable production Oracle databases to survive disasters and data corruptions. Data Guard maintains these standby databases as transactionally consistent copies of the production database.
What is Data Guard background process?
The Data Guard monitor process (DMON) is an Oracle background process that runs for every database instance that is managed by the broker. When you start the Data Guard broker, a DMON process is created.
What are the advantages in using Oracle Data Guard?
Advantages. Data Guard provides high availability for a database system. It can also reduce the human intervention required to switch between databases at disaster-recovery (“failover”) or upgrade/maintenance (“switchover”) time. Through the use of standby redo log files, Data Guard can minimize data loss.
What is the difference between switchover and fail over?
Answer: In general, a failover is a production emergency, where the primary database has failed and you need to failover to the standby database. Conversely, a switchover is a planned switch from a standby back to the primary database, a non-emergency operation.
What is the meaning of switchover in firing?
Switchover is the manual switching of a terminated system upon occurrence of an error.
What is LNS and RFS in dataguard?
LNS process of primary database captures redo from redo log buffer. Send it to RFS process of standby database through oracle net. RFS process then writes that redo information to standby redo log files.
What is RFS in Data Guard?
Remote file server (RFS) The remote file server process receives redo data from the primary database. The RFS process communicates with the logical standby process (LSP) to coordinate and record which files arrived.
What is Fal_client and Fal_server in Oracle?
FAL_SERVER used to fetch archive log server for a standby database. Value in FAL_SERVER parameter act as Oracle Net Service name which point to standby database. FAL_CLIENT Parameter. FAL_CLIENT specifies the FAL(fetch archive log) client name that is used by the FAL service. It configured for point the FAL Client.
What is switchover for firing?
How do you failover in Oracle Data Guard?
On the Oracle Data Guard Overview page in Cloud Control, select the standby database that you want to change to the primary role and click Failover. Then, on the Failover Confirmation page, click Yes to invoke the default Complete failover option.
What is a DB failover?
Failover is a backup operational mode that automatically switches to a standby database, server or network if the primary system fails, or is shut down for servicing. Failover is an extremely important function for critical systems that require always-on accessibility.
What is the difference between Active Data Guard and Data Guard?
Data Guard is a feature of the Oracle Database Enterprise Edition itself and does not require separate licensing. On the other hand, Active Data Guard is a so-called Oracle Database Enterprise Edition Option and as such requires separate licensing.
What is RFS in Oracle Data Guard?
Remote file server (RFS) The remote file server (RFS) process receives redo data from the primary database either in the form of archived redo logs or standby redo logs.
What is LNS and RFS in Data Guard?
What is RFS and MRP?
The remote file server (RFS) process receives redo data from the primary database either in the form of archived redo logs or standby redo logs. Archiver (ARCn) If standby redo logs are being used, the ARCn process archives the standby redo logs that are to be applied by the managed recovery process (MRP).
What are the types of Data Guard?
An Oracle Data Guard configuration can include any combination of these types of standby databases….2.1 Standby Database Types
- 1 Physical Standby Databases. A physical standby database is an exact, block-for-block copy of a primary database.
- 2 Logical Standby Databases.
- 3 Snapshot Standby Databases.
What are the questions related to Oracle Data Guard?
Some of the Oracle Data Guard related questions are listed below. What is data guard in simple language? Your primary database is running and you want to reduce downtime because of unplanned outages. You create a replica of this primary database (termed as standby database).
What is Data Guard?
Data Guard provides a comprehensive set of services that create, maintain, manage, and monitor one or more standby databases to enable production Oracle databases to survive disasters and data corruptions. Data Guard maintains these standby databases as copies of the production database.
What’s new in Data Guard 11g?
With 11g, you can thoroughly test your changes on a true replica of your production system and database using actual production workload. Data Guard 11g physical standby can now be converted to a snapshot standby, independent of the primary database, that is open read-write and able to be used for preproduction testing.
What is Oracle Active Data Guard (ADG)?
Oracle Active Data Guard enables read-only access to a physical standby database for queries, sorting, reporting, web-based access, etc., while continuously applying changes received from the production database.