Featured Post

Step-by-Step Guide to Creating an AWS RDS Database Instance

-
Image
 Amazon Relational Database Service (AWS RDS) makes it easy to set up, operate, and scale a relational database in the cloud. Instead of managing servers, patching OS, and handling backups manually, AWS RDS takes care of the heavy lifting so you can focus on building applications and data pipelines. In this blog, we’ll walk through how to create an AWS RDS instance , key configuration choices, and best practices you should follow in real-world projects. What is AWS RDS? AWS RDS is a managed database service that supports popular relational engines such as: Amazon Aurora (MySQL / PostgreSQL compatible) MySQL PostgreSQL MariaDB Oracle SQL Server With RDS, AWS manages: Database provisioning Automated backups Software patching High availability (Multi-AZ) Monitoring and scaling Prerequisites Before creating an RDS instance, make sure you have: An active AWS account Proper IAM permissions (RDS, EC2, VPC) A basic understanding of: ...
Post a Comment

How to Configure Firewall For an Application

-
A firewall is a set of rules. When a data packet moves into or out of protected network space, its contents (in particular, information about its origin, its target, and the protocol it plans to use) are tested against the firewall rules to see if it should be allowed through.


Firewall configuration


How a Firewall concept works

Let's say that the web server has to be open to incoming web traffic from anywhere on earth using either the insecure HTTP or secure HTTPS protocol.

Because your developers and admins will need to get into the backend from time to time to do their work, you’ll also want to allow SSH traffic, but only for those people who’ll need it. Requests for any other services should be automatically refused.

A Linux machine can be configured to apply firewall rules at the kernel level through a program called iptables.

Creating table rules isn't all that difficult; the syntax can be learned without too much fuss. But, in the interest of simplifying your life, many Linux distributions have added their own higher-level tools for abstracting the job.


Firewall functionality


It is also available through hardware appliances manufactured by companies like Juniper and Cisco. Those proprietary devices run on their own operating systems with unique syntax and design.

For larger enterprise deployments involving hundreds of servers spread across multiple networks, such tools will often make a lot of sense, but there's a remarkable amount that you can accomplish with any old Linux box for a tiny fraction of the cost. 


Firewall


As you might have guessed from its name, firewalld is part of the systemd family. firewalld can be installed on Debian/Ubuntu machines, but it's there by default on Red Hat and CentOS. If you're just too excited by firewalld to even consider trying anything else, here's how to install it and get it running on Ubuntu:

# apt update # apt install firewalld

To confirm that the firewall is working, try browsing your server's web root. If the site is unreachable, then firewalld is doing its job.

You’ll use the firewall-cmd tool to manage firewalld settings from the command line. Adding the --state argument returns the current firewall status:

# firewall-cmd --state running

Related

Comments

Post a Comment

Thanks for your message. We will get back you.

Popular posts from this blog

Step-by-Step Guide to Reading Different Files in Python

-
Image
 In the world of data science, automation, and general programming, working with files is unavoidable. Whether you’re dealing with CSV reports, JSON APIs, Excel sheets, or text logs, Python provides rich and easy-to-use libraries for reading different file formats. In this guide, we’ll explore how to read different files in Python , with code examples and best practices. 1. Reading Text Files ( .txt ) Text files are the simplest form of files. Python’s built-in open() function handles them effortlessly. Example: # Open and read a text file with open ( "sample.txt" , "r" ) as file: content = file.read() print (content) Explanation: "r" mode means read . with open() automatically closes the file when done. Best Practice: Always use with to handle files to avoid memory leaks. 2. Reading CSV Files ( .csv ) CSV files are widely used for storing tabular data. Python has a built-in csv module and a powerful pandas library. Using cs...
Read more

SQL Query: 3 Methods for Calculating Cumulative SUM

-
Image
SQL provides various constructs for calculating cumulative sums, offering flexibility and efficiency in data analysis. In this article, we explore three distinct SQL queries that facilitate the computation of cumulative sums. Each query leverages different SQL constructs to achieve the desired outcome, catering to diverse analytical needs and preferences. Using Window Functions (e.g., PostgreSQL, SQL Server, Oracle) SELECT id, value, SUM(value) OVER (ORDER BY id) AS cumulative_sum  FROM your_table; This query uses the SUM() window function with the OVER clause to calculate the cumulative sum of the value column ordered by the id column. Using Subqueries (e.g., MySQL, SQLite): SELECT t1.id, t1.value, SUM(t2.value) AS cumulative_sum FROM your_table t1 JOIN your_table t2 ON t1.id >= t2.id GROUP BY t1.id, t1.value ORDER BY t1.id; This query uses a self-join to calculate the cumulative sum. It joins the table with itself, matching rows where the id in the first table is greater than...
Read more

PowerCurve for Beginners: A Comprehensive Guide

-
Image
PowerCurve is a complete suite of decision-making solutions that help businesses make efficient, data-driven decisions. Whether you're new to PowerCurve or want to understand its core concepts, this guide will introduce you to chief features, applications, and benefits. What is PowerCurve? PowerCurve is a decision management software developed by Experian that allows organizations to automate and optimize decision-making processes. It leverages data analytics, machine learning, and business rules to provide actionable insights for risk assessment, customer management, fraud detection, and more. Key Features of PowerCurve Data Integration – PowerCurve integrates with multiple data sources, including internal databases, third-party data providers, and cloud-based platforms. Automated Decisioning – The platform automates decision-making processes based on predefined rules and predictive models. Machine Learning & AI – PowerCurve utilizes advanced analytics and AI-driven models ...
Read more