Today's Learnings - 30 Dec

Encompass : •(verb) include in scope; include as part of something broader; have as one's sphere or territory
"This group encompasses a wide range of people from different backgrounds", "this should cover everyone in the group"
synonyms : comprehend , cover , embrace

protagonist:
A protagonist (from the Greek p??ta????st?? protagonistes, "one who plays the first part, chief actor"[1]) is the main character (the central or primary personal figure) of a literary, theatrical, cinematic, video game, or musical narrative, around whom the events of the narrative's plot revolve and with whom the audience is intended to share the most empathy. In the theatre of Ancient Greece, three actors played all of the main dramatic roles in a tragedy; the leading role was played by the protagonist, while the other roles were played by deuteragonist and the tritagonist.

2.1 Oracle High Availability Features
Oracle provides the following features for high availability:
•Oracle Real Application Clusters
•Oracle Data Guard
•Oracle Streams
•Oracle Flashback Technology
•Automatic Storage Management
•Recovery Manager
•Flash Recovery Area
•Oracle Security Features
•Fast-Start Fault Recovery
•LogMiner
•Hardware Assisted Resilient Data (HARD) Initiative

2.5 High Availability Management
Oracle Enterprise Manager Grid Control is an HTML-based user interface that provides the administrator with complete monitoring across the entire Oracle technology stack—business applications, application servers, databases, and the E-Business Suite—as well as non-Oracle components within the Grid. If a component within the Grid becomes unavailable or experiences performance problems, an alert is automatically generated to the Enterprise Manager console to inform the administrator so appropriate action can be taken.

The components of the Oracle Enterprise Manager Grid Control include:

•Oracle Management Service (OMS) - a J2EE Web application that renders the user interface for the Grid Control Console, works with all Management Agents to process monitoring information, and uses the Management Repository as its persistent data store

•Oracle Management Agents - processes deployed on each monitored host to monitor all targets on the host, communicate that information to the Management Service, and maintain the host and its targets

•Oracle Management Repository - schema in the Oracle database that contains all available information about administrators, targets, and applications managed by Enterprise Manager

Communication between the console, the OMS, and Oracle Management Agents is done through HTTP. SSL can also be enabled to allow secure communications between tiers within firewall-protected environments. The Management Agent uploads collected monitoring data to the OMS, which in turn loads the data into the Management Repository. Changes in a target state (such as an availability state change) result in an alert being generated to the Enterprise Manager Console.

Using Oracle Enterprise Manager Grid Control, an administrator can:
•Monitor architecture components and be alerted when a failure occurs
•View overall system status, such as the number of nodes in the database cluster and their current status
•View alerts aggregated across all instances
•Set thresholds for alert generation on a database cluster-wide basis
•Monitor performance metric across all instances
•Perform database cluster-wide operations such as backup and recovery
•Viewing hardware and operating system information in the entire Grid as a whole
•Interconnect monitoring of cluster databases