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15 slacknesses or lack of experience that can come back & bite you in the back

Production issues seek the attention of middle and top level management. Often these are intermittent issues that are harder to reproduce in lower environments without the right know-hows & tools. Some will shrug it off as “Cannot be reproduced“, whilst others will seize the opportunity to showcase their technical strengths & know hows to go places. Here are a few things that you must pay attention as a software developer, designer or architect to prevent any future embarrassments. You can use this as a check list.

#1: Not externalizing configuration values in config file(s) (E.g: .properties, .xml, …

Auditing database record changes in Oracle

Q. What are some of the considerations in auditing database table data? A. Creating audit tables without any constraints to store record changes.  Audit tables are heavily hit with inserts, hence needs to have fewer indices if at all required. Decide on what combination of triggers are required like  Create,…


Auditing, data retention and archiving interview Q&As

Q1 What are some of the considerations in auditing database table data? A1 1) Tables are created with auditable columns like created_by, created_date, updated_by, and updated_date, and synch_date or timestamp. You can also have a version column. Thes fields are handy to track changes. The version and timestamp columns are…

How do you monitor the JVM?

Since Java SE 5.0, the JRE provides a mean to manage and monitor the Java Virtual Machine. It comes in two flavors: The JVM has built-in instrumentation that enables you to monitor and manage it using Java Management eXtension (JMX). You can also monitor instrumented applications with JMX. To start…

Monitoring/Profiling Java applications interview Q&A

Q1 How will you go about monitoring your Java application for potential performance or memory issues? A1 1. Visual VM for monitoring Java memory, CPU, threads, etc VisualVM is a visual tool integrating several command-line JDK tools and lightweight profiling capabilities. Designed for both production and development time use, it…

QoS & SLAs interview Q&As on Availability, Serviceability, Fault tolerance & Disaster Recoverability – Non Functional Requirements

Q1. What are the system qualities that typically form a basis for QoS requirements? A1. Quality of service (QoS) covers Non Functional requirements such as As microservices use disparate datasources like SQL store, NoSQL store, Cache, Object store like AWS S3, etc you need to map non functional requirements to…


Splunk to analyse Java logs and other machine data

Q1. What is Splunk and where will you use it?
A1. Splunk is an enterprise-grade software tool for collecting and analyzing “machine data” like log files, feed files, and other big data in terra bytes. You can upload logs from your websites and let Splunk index them, and produce reports with graphs to analyze the reports. This is very useful in capturing start and finish times from asynchronous processes to calculate elapsed times. For example, here are the basic steps required.

Step 1: log4j MDC logging can be used to output context based logs and then
Step 2:

Understanding service and socket timeouts in Java enterprise applications

Q. Why is it important to set proper timeout values in your applications?
A. Security and performance.

Security reason: it is often necessary to control how long a Web Service client or other valuable clients invoking valuable resources like database connections, transaction management, etc waits for a response after sending a request. Not setting proper timeouts can be a potential candidate for DoS attacks, especially via web service calls. This is why the application servers provide various timeout configurations to prevent DoS (Denial of Service) attacks. For example, in application servers

  • The RequestReadTimeout allows to limit the time

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