This post describes how to monitor SGA memory usage on pluggable databases using queries against database views. Pre-requisites to using the sample code provided below are: On RAC configuration, the scripts should be run on each instance since only V$ views are used to provide an accurate memory usage for the individual database instance. The scripts must be run in SQL*Plus session since specific SQL*Plus functions are used. Scripts must be run as sysdba or database user account having … [Read more...] about How to Monitor SGA Memory on Oracle Pluggable Databases
oracle 12c
How To Automate The Opening Of Pluggable Databases After The CDB Starts Up in Oracle 12c
Here is a short note on how to automate the startup of PDBs after the CDB starts up in Oracle database 12c. You can start all the PDBs or selective PDBs using below steps. We will need to create a database startup trigger in order to automate the PDB startup. Follow the steps outlined below. 1. Login into the CDB as sysdba. $ sqlplus / as sysdba 2. Create a database startup trigger to open all pluggable databases. create or replace trigger open_all_pdbs after startup on … [Read more...] about How To Automate The Opening Of Pluggable Databases After The CDB Starts Up in Oracle 12c
Oracle 12.2 : RMAN Cross-Platform Transport of PDB into Destination CDB
Introduction and Pre-requisites Using RMAN, Pluggable database (PDBs) can be transported and plugged into a destination multitenant container database (CDB) which is on a different platform than the source CDB. In addition to the backup of the PDB, RMAN also copies the metadata required to plug the PDB into the destination CDB. The source CDB and the destination CDB must use the same endian format. Below steps show migration of closed PDB from source platform Solaris (Big Endian) to AIX (Big … [Read more...] about Oracle 12.2 : RMAN Cross-Platform Transport of PDB into Destination CDB
Automatic Stop of Oracle Database (dbshut) not working in CentOS/RHEL 7 with systemd
The Problem On CentOS/RHEL 7 with Oracle database 12.1.0.2 version, when attempting to stop DB during server shutdown the automatic shutdown script getting below error: # cat /u01/app/oracle/product/12.1.0.2/dbhome_1/shutdown.log Processing Database instance "XXXX1": log file /u01/app/oracle/product/12.1.0.2/dbhome_1/shutdown.log Info: Database instance "XXXX" already down (PMON process not there). Which indicate that PMON is forcefully being closed before the script is called. This is … [Read more...] about Automatic Stop of Oracle Database (dbshut) not working in CentOS/RHEL 7 with systemd
How to Monitor Process Memory Usage on Oracle Pluggable Databases
The purpose of this post is to demonstrate how to determine process memory usage of pluggable databases. Pre requisites - On RAC configuration, the scripts should be run on each instances since only V$ views are used to provide a accurate memory usage for individual database instance. - The scripts must be run in SQL*Plus session since specific SQL*Plus functions are used. - Scripts must be run as sysdba or database user account having access to CDB*, DBA* and V$ tables. - Example … [Read more...] about How to Monitor Process Memory Usage on Oracle Pluggable Databases
How to Extend ocfs2 Filesystem with tunefs.ocfs2 Command (Whole device used without partitions)
The below process works only for an ocfs2 file-system created on whole device (with no partitions used): 1. Make sure that an ocfs2 backup is present before continuing. 2. Prepare global outage to extend the ocfs2 fs. 3. Unmount the share on all nodes using it (for safety reasons, such as avoiding data corruption if a node writes to the device when the disk extend is being performed) 4. Make sure that the new LUN size is visible under OS (using any scsi rescan command) on all … [Read more...] about How to Extend ocfs2 Filesystem with tunefs.ocfs2 Command (Whole device used without partitions)
Oracle ASM 12c – New Features with examples
This post discusses a few 12C ASM new features with examples: Failgroup_repair_time Online disk replace Estimate Work V$ASM_OPERATION view 1. FAILGROUP_REPAIR_TIME For earlier ASM versions, we had disk_repair_time, from 12C onwards we have failgroup_repair_time at the ASM level. Because failure group outages are more likely to be transient in nature and because replacing all the disks in a failure group is a much more expensive operation than replacing a single disk, it would … [Read more...] about Oracle ASM 12c – New Features with examples
Oracle Database 12c New Feature – RMAN “RECOVER TABLE”
Table recovery Table recovery was possible in earlier releases as well. Until previous releases, if we wanted to recover a table, we had the following options: Database point in time recovery (DBPITR) Tablespace point in time recovery (TSPITR) Flashback technology The RECOVER TABLE command is a new feature in 12C that allows a point in time recovery of a table or a table partition. The table is recovered into an auxiliary instance and there is the option to: import the recovered … [Read more...] about Oracle Database 12c New Feature – RMAN “RECOVER TABLE”
Interview Questions : Oracle Flex ASM 12c
What is Oracle Flex ASM? Oracle Flex ASM is an ASM instance which will be running in the cluster based on cardinality defined. The default cardinality is three, but you can change it using srvctl modify asm command. It means that ASM is not required to run on each node in the cluster. In the previous release, ASM will be running on each node in the cluster and ASM clients (Database, ACFS, ADVM) can only access ASM by using an ASM on the same host. With Oracle Flex ASM, the clients can … [Read more...] about Interview Questions : Oracle Flex ASM 12c
Oracle sql script to report the list of files stored in ASM and CURRENTLY NOT OPENED
Purpose One of the features of ASM is databases consolidation. A single diskgroup will be the repository for multiple databases. The result, having a large number of datafiles. If the files were created using OMF (Oracle Managed Files) format, when the datafile is deleted on the database side, it is also deleted on the ASM side. There may be situations when the datafiles are not deleted on the ASM side, particularly when not using OMF format. With large diskgroups holding large number of … [Read more...] about Oracle sql script to report the list of files stored in ASM and CURRENTLY NOT OPENED