What is Split-Brain? The term “Split-Brain” is often used to describe the scenario when two or more co-operating processes in a distributed system, typically a high availability cluster, lose connectivity with one another but then continue to operate independently of each other, including acquiring logical or physical resources, under the incorrect assumption that the other […]
Interview Questions
Linux Interview Questions – Linux Printing (CUPS)
This post covers the most often asked how-to questions about Linux printing support. What tool provides Linux printing support? CUPS, the Common Unix Printing System What kinds of printers can be attached to a Linux system? Linux support printers which are connected using any of the following: Locally Attached Printer (LPT) through a local parallel […]
Oracle Interview Questions – Flash Recovery Area
Naming convention: Oracle 10g: FLASH Recovery Area Oracle 11g: FAST Recovery Area 1. What is a Flash Recovery Area ? The flash recovery area is an Oracle-managed directory, file system, or Automatic Storage Management disk group that provides a centralized disk location for backup and recovery files. All the files you need to completely recover […]
Oracle RMAN interview questions
General RMAN Questions What is RMAN and How to configure it? RMAN is an Oracle Database client that performs backup and recovery tasks on your databases and automates the administration of your backup strategies. It greatly simplifies the dba jobs by managing the production database’s backing up, restoring, and recovering database files. This tool integrates […]
Oracle Interview Questions : Recovery catalog for RMAN backup
Why use a recovery catalog? The RMAN catalog has several benefits. It makes restore if all the target database is lost, including the controlfile. As that controlfile contains all backup information, the catalog would then be used to identify a controlfile backup. If an RMAN catalog is not used, the controlfile autobackup should be configured […]
Oracle Interview Questions : Grid Infrastructure Single Client Access Name (SCAN)
SCAN Concepts Single client access name (SCAN) is the virtual hostname to provide for all clients connecting to the cluster (as opposed to the VIP hostnames in 10g and 11gR1). SCAN is a domain name registered to at least one and up to three IP addresses, either in the domain name service (DNS) or the […]
MySQL Interview Questions : Multi-source Replication in MySQL Server
Can I upgrade my slave from 5.6 to 5.7 and connect more masters to it? When upgrading so that the master version is lower/earlier than the slave version there is always a large risk it will not work. This is because newer versions may have made incompatible changes that means the older version will not […]
Linux Interview Questions – Basic File and Directory Permissions
What are Basic Linux File permissions? Linux, like UNIX, is a multi-user system, and file permissions are one way the system protects against malicious tampering. One way to gain entry when you are denied permission is to su to root. Keep in mind, whoever knows the root password has complete access. But switching to the […]
Oracle Database Interview Questions : Redo Logs and Archiving
What is the Redo Log? Redo Logs consist of two or more pre-allocated files that store all changes made to the database as they occur. Every instance of an Oracle Database has associated online redo logs to protect the database in case of an instance failure. Redo log files are filled with redo records. A […]
Interview Questions : Oracle 12c Multitenant Database Architecture
General CDB / PDB Concept in 12c Multitenant Architecture What is a pluggable database (PDB) in Multitenant Architecture? Pluggable Databases (PDBs) is new in Oracle Database 12c Release 1 (12.1). You can have many pluggable databases inside a single Oracle Database occurrence. Pluggable Databases are fully backwards compatible with an ordinary pre-12.1 database. Why would […]