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VPC Flow Logs

Hi there! I wanted to share some valuable insights with you about AWS Flow Logs, which can be an invaluable tool in working with AWS cloud.

What are AWS Flow Logs?

AWS Flow Logs is a mechanism that allows users to monitor network traffic within the AWS infrastructure. It's somewhat like a "black box" for the cloud - it records where the traffic is coming from, where it's going, and how much data it's transmitting. Flow log data can be published to the following locations: Amazon CloudWatch Logs, Amazon S3, or Amazon Data Firehose

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Key Benefits:

  • Easier Troubleshooting: When something isn't working as it should, Flow Logs help you find the root cause of the problem. Sometimes, just a glance at the network traffic data is enough to find the source of the issue.
  • Enhanced Security: With Flow Logs, you can quickly detect and analyze suspicious or unauthorized network activities.
  • Performance Optimization: Understanding the dynamics of network traffic is key to optimizing the performance of applications and services in the cloud. With Flow Logs, you can identify "bottlenecks" in the infrastructure and optimize its performance.

Flow log records

The flow log records represent network flows within your VPC. By default, each record captures an IP traffic flow. These records are formatted as strings with fields separated by spaces, containing for example information such as the source, destination, port and protocol of the flow. When setting up a flow log, you have the option to use the default format or specify a custom one.

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How to Start Using AWS Flow Logs?

The best part is that you can enable Flow Logs yourself, with minimal effort. Just use the AWS console or command-line tools to activate this feature at the VPC, subnet, or network interface level.

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You can watch my video tutorial on YouTube, which shows step by step what exactly needs to be done. Which IAM policy to choose, what IAM role. How to create a Log group in CloudWatch and how to save logs from network interfaces there. I walk you through how to use AWS Flow Logs and interpret the collected data step by step. It's a great way to deepen your knowledge of the AWS cloud.


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