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I have just came across a meta parameter called DB_ULTRA_SAFE that sets the values for all of mentioned parameters in Far Sync Best Practice Recommendations (for Oracle 12.1) . When DB_ULTRA_SAFE=DATA_ONLY   • DB_BLOCK_CHECKING => MEDIUM.   • DB_LOST_WRITE_PROTECT => TYPICAL.   • DB_BLOCK_CHECKSUM => FULL. When DB_ULTRA_SAFE=DATA_AND_INDEX   • DB_BLOCK_CHECKING => FULL.   • DB_LOST_WRITE_PROTECT => TYPICAL.   • DB_BLOCK_CHECKSUM => FULL. When DB_ULTRA_SAFE=OFF   • When any of DB_BLOCK_CHECKING, DB_BLOCK_CHECKSUM, or DB_LOST_WRITE_PROTECT are explicitly set, no changes are made.

Hi, At Oracle Open World 2017 I collected the main improvements and changes  are going to be implemented in Oracle Database 18c: RMAN - Refresh a standby from primary/backup using single RECOVER command Data Guard - In Memory Column store works with multi-instance redo apply - Multi-instance redo apply support with Block Change Tracking (BCT) - Global Temporary Table support from Standby. - DML operations on Standby – Redirection to Primary without ACID compromise. - Preserve buffer cache during role-change. - No logging enhancement - Performance mode and Availability mode. Yossi Nixon

The bottom line: Oracle are inventing aggressively on PaaS and starting to neglect the IaaS.  They are doing it by: - Reducing price of the PaaS. - More automation to reduce dramatically the TCO (migration to cloud, patches, upgrades, tuning)  - Higher performance.  - Simpler pricing and contract (a pool of cloud cedits you can use for anything)  - New autonomous database will be commercial soon. - You can bring your own license.  And again Oracle claim that their cloud is  faster than Amazon   for database   with much lower price.

These are the steps of creating Far Sync instance in the command line: Create 12.1 primary db Create 12.1 physical standby Create regular standby DG broker configuration modify network file (on primary and standby) and add entries for the far_sync instance, add to tnsnames.ora on Primary hosts and standby hosts: FarSyncInst =   (DESCRIPTION =     (ADDRESS_LIST =       (ADDRESS = (PROTOCOL = TCP)(HOST = FarSyncHost)(PORT = 1521))     )     (CONNECT_DATA =       (SERVER = DEDICATED)       (SERVICE_NAME = FarSyncInst)       (UR=A)     )   )     Note: (UR=A) is needed to connect to a BLOCKED unmounted database instance. Copy tnsnames.ora to new farsync server – ensure all hosts mentioned in tnsnames are written also in /etc/hosts Add to listener.ora in far sync server LISTENER =   (DESCRIPTION_LIST =     (DESCRIPTION =     ...

Connection manager is working as oracle SQL*NET proxy and firewall. In this example, I am using Connection Manager of Oracle Database 12c Release 2 running on Linux x86_64 Footprint Storage: 1.7 G Memory: 5~28.4 MB Requires: Installation of Oracle Client in a separated folder than the database software Register the connection manager in the grid infrastructure as a cluster resource Configure and install on the intermediate host Download Oracle Database 12c Release 2 Client unzip linuxx64_12201_client.zip Change response file /client/response/client_install.rsp: UNIX_GROUP_NAME= INVENTORY_LOCATION= ORACLE_HOME= ORACLE_BASE= oracle.install.client.installType=Custom oracle.install.client.customComponents=oracle.network.cman:12.2.0.1.0 Start silent installation: cd /client ./runInstaller -silent -responseFile /client/response/client_install.rsp -ignoreSysPrereqs -ignorePrereq -noconfig -waitforcompletion -force -showProgress run root.sh sudo /oracle/prod...

Hi, This post is a continuation of my post, Using Standby as an Alternate for Far Sync (12c): Limitations and Considerations . It is for database administrators who want to set up Far Sync for the first time. Creating a Far Sync instance requires a number of manual steps and there are many parameters to consider or set. I recently ran numerous scenarios using Oracle™ Active Data Guard with a Far Sync instance. Our goals were to: • Check Far Sync functionality and reliability • Validate that Far Sync has a low footprint under heavy load After running a large number of benchmark scenarios, where we changed one parameter at a time, here are my recommendations for using Active Data Guard with Far Sync: The primary database, the standby database, and the Far Sync instance should all be using the same software version and patch level; if not, upgrade the database(s) to the latest version with the latest patch sets. Consider changing the following database initialization parameters...

When changing IP of a host we should update/recheck the following places: /etc/hosts or DNS listener.ora tnsnames.ora Database parameters (local_listener, remote_listener) Data Guard configuration This document is also relevant when changing the IP address of the connection between the hosts, other than the original IP addresses we used during the installation. When installation is done using the hostname and not the IP address, most of the changes are not relevant except for /etc/hosts. In this document, I will describe how to change the Data Guard Broker configuration. Dataguard configuration Show the environment DGMGRL> show configuration Configuration - dr   Protection Mode: MaxAvailability   Members:   pdb7 - Primary database     fdb7 - Far sync instance       sdb7 - Physical standby database Fast-Start Failover: DISABLED Configuration Status: SUCCESS   (status upd...

As a DBA, I find myself trying to support customers remotely, who frequently ask for another Automatic Workload Repository (AWR) or a special query. I’ve found a cool feature that enables customer's DBAs to extract the AWR and then load it locally. Extracting 1. Login as SYS and at the SQL prompt, enter: SQL> @?/rdbms/admin/awrextr.sql 2. Enter your database id or press <Enter> to use the current default. Enter value for dbid: Using 3342354369 for Database ID 3. Specify the number of days for which you want to list snapshot Ids. Enter value for num_days: 14 4. After the list displays, enter the beginning and ending snapshot ID. Enter value for begin_snap: 2670 Enter value for end_snap: 2672 5. A list of directory objects is displayed. Specify the directory object pointing to the directory where the export dump file will be stored. Enter value for directory_name: DATA_PUMP_DIR 6. Specify the prefix for the default dump file name ...

How to display AWR snapshot settings Oracle database is gathering statistics periodically (snapshots), these statistics can be used for analyzing database performance. These statistics are kept in the Automatic Workload Repository (AWR).  Retention Interval: Amount of time to keep the snapshots. Snapshot Interval: How often to automatically take snapshots. SELECT 'Snapshot Interval' "Interval" ,      EXTRACT ( DAY FROM snap_interval ) days ,      EXTRACT ( HOUR FROM snap_interval ) hours ,      EXTRACT ( MINUTE FROM snap_interval ) minutes   FROM dba_hist_wr_control UNION ALL SELECT 'Retention Interval' "Interval" ,      EXTRACT ( DAY FROM retention ) days ,      EXTRACT ( HOUR FROM retention ) hours ,      EXTRACT ( MINUTE FROM retention ) minutes   FROM dba_hist_wr_contr...

Based on Oracle 12.1 The Recommended Data Guard configuration is in Maximum Availability mode, when using Far Sync which is located near the Primary: Primary Database  à Far Sync Instance - Network input/output (I/O) is synchronous (Sync). Far Sync Instance  à  Standby Database – Network I/O is asynchronous (Async). Primary Database  à  Standby Database  – As an alternate (when Far Sync is not reachable), network I/O is asynchronous (Async). Using SQL If you do not use Data Guard Broker (dgmgrl), use the parameters specified below. ·         Primary On the Primary Database Mandatory Parameters Parameter Value Remarks LOG_ARCHIVE_DEST_2 point to Far Sync service Alternate log_archive_dest_3 Switches to the standby destination, after the number of failures specified in the next parameter is reached. max_failure 1 This val...