Learning With Nitin Kumar

Steps need to be performed:  On the Syslog server side:  1. Install the rsyslog sudo yum install rsyslog 2.  Enable rsyslog service: Start and enable the rsyslog service if it’s not already running: sudo systemctl start rsyslog sudo systemctl enable rsyslog 3.  Configure rsyslog to accept remote logs: Open the rsyslog configuration file: vi /etc/rsyslog.conf Uncomment or add the following lines to enable UDP or TCP log reception: # Provides UDP syslog reception module(load="imudp") input(type="imudp" port="514") # Provides TCP syslog reception module(load="imtcp") input(type="imtcp" port="514") 4.  Restart the rsyslog service: After saving the configuration file, restart rsyslog to apply the changes: sudo systemctl restart rsyslog 5. Ensure the firewall is configured to allow the TCP/UDP port 514 or disable the firewall service. 6. Ensure that SELinux is disable if not disable it Check the status of SELinux sestatus Disa...

Crontab (short for "cron table") is a configuration file in Unix-like operating systems that specifies shell commands to run periodically on a given schedule.  The commands are executed by the cron daemon, a system process that runs in the background. Crontab allows users to automate repetitive tasks such as backups, updates, and scheduled maintenance. Components of Crontab Each line in the crontab file consists of two parts: Timing information : Specifies when the command should run. Command : The shell command to execute. The timing information is divided into five fields: Minute (0-59) Hour (0-23) Day of the month (1-31) Month (1-12) Day of the week (0-7, where both 0 and 7 represent Sunday) Note : The fields can be filled with numbers, ranges, lists, or special characters like * , which means "every" value for that field. Crontab Format: * * * * * command_to_run | | | | |  | | | | +---- Day of the week (0-7) | | | +------ Month (1-12) | | +-------- Day of ...

  What is an API Call? An **API call** involves sending a request to an API (Application Programming Interface) and receiving a response. This is done to interact with a server or service programmatically. API calls are commonly used for: Components of an API Call 1. **Endpoint**:  The specific URL or URI where the API request is sent. It defines the resource you want to access or manipulate. 2. **HTTP Method**(Type of HTTP request):  The type of operation you want to perform. Common methods include: - **GET**: Retrieve data from server. - **POST**: Send new data or create a resource to server. - **PUT/PATCH**: Update existing data. - **DELETE**: Remove data. 3. **Headers**:  Metadata sent with the request, such as content type or authentication tokens. 4. **Body**:  Data sent with the request (usually with POST or PUT requests), typically in JSON format. 5. **Response** : The data or result returned by the server after processing the request. Note:  In Con...

  curl is a command-line tool for making HTTP requests to web servers.

 What is OSI Model? The OSI (open system interconnection) model, created in 1984 by ISO, is a reference framework that explains the process of transmitting data between computers. Layers of OSI Model OSI model has seven layers, which are as follows: 1. The Physical Layer 2. The Data Link Layer 3. The Network Layer 4. The Transport Layer 5. The Session Layer 6. The Presentation Layer 7. The Application Layer 1.  Application Layer – Layer 1 (considering we are on sender side ) · User work on app layer. · App layer provide the interface to user like Gmail. · At the very top of the OSI Reference Model stack of layers, we find the Application layer, which is implemented by the network applications. These applications produce the data, which has to be transferred over the network. This layer also serves as a window for the application services to access the network and for displaying the received information to the user. Example: Application – Browsers, Skype Messenger, Gmail, outl...

My SQL Database It is an organized collection of data so that it can be easily accessed. To mannage these database, DBMS are used. Type of DBMS Relational DBMS Non-Relational DBMS Relational DBMS: In this, data will be stored in table format. Example: MYSQL, Oracle Non-Relational DBMS: In this, data will be stored in key-value pair. like: { “RollNo”:1, “Name”: “abc”, “Class”: 2 } Example : MongoDB, Redis SQL:  It stand for structure query language. It is used for update, delete, insert the datain table. Data Type in MYSQL: 1. Numeric Data Types INT: Integer type, ranges from -2147483648 to 2147483647. FLOAT : Floating-point number, with optional precision. DOUBLE: Double-precision floating-point number. DECIMAL: Fixed-point number with defined precision and scale. TINYINT: Small integer, ranges from -128 to 127. SMALLINT: Smaller integer, ranges from -32768 to 32767. MEDIUMINT: Medium-sized integer, ranges from -8388608 to 8388607 2.String Data Types CHAR: Fixed-length cha...

 FileSystem A filesystem is a method used by operating systems to organize and store data on storage devices such as hard drives, solid-state drives (SSDs), USB drives, and other storage media. It provides a structured way to store, retrieve, and manage files and directories within a storage device. Key characteristics and functionalities of a filesystem include: Hierarchical Structure: Filesystems organize data in a hierarchical structure consisting of directories (also known as folders) and files. Directories can contain other directories (subdirectories) and files, forming a tree-like structure. File Naming: Each file within a filesystem is identified by a unique name, which allows users and applications to access and manipulate individual files. File Attributes: Filesystems typically store additional information, known as metadata, about each file, including attributes such as file size, creation date, modification date, and permissions. Data Storage: Filesystems manage the a...