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AWS Shield/Shield Advanced AWS Shield is layer-4 protection, defending you from DDOS attacks like SYN flood, UDP floods or other reflection attacks. It does that by setting static thresholds and implementing Inline attack mitigation. AWS Shield Advanced adds more advanced detection and mitigation mechanisms, together …

What are Data Streams Data streams refer to continuous flows of data that are generated continuously over time Data streams are continuous and potentially infinite in nature. Data streams can originate from various sources such as: sensors social media feeds financial transactions website clickstreams etc. …

(this document is a work-in-progress, it is not complete, so you should visit this document from time to time to see if anything has changed) The AWS Solution Architect Associate exam content contains these sections: Domain 1: Design Secure Architectures (30%) 1.1: Design secure access to AWS resources. Cross account …

Python Virtual Environments If you're running myltiple python project on your computer, you may want use a tool that handles python virtual environments, for reasons such as: be able to install different libraries and modules for each project Use different versions of python for different projects This is especially …

What is DNS Informally, we could say that DNS (Domain Name System) allows users to use names instead of IP addresses. The initial thinking was that names are easier to remember and work with, so users will find it easier to use them. In fact, DNS is part of the network itself. For example, you could run a single …

About Parameter Expansion This post is based on th shell parameter expansion documentation. The ‘$’ character introduces several expansions: parameter expansion command substitution arithmetic expansion Parameter expansion mainly replaces a parameter reference with its value. When we're talking about shell parameters …

About tilde expansion This post is based on the bash tilde expansion documentation. Let's say that you enter several letters, and them the ~ (tilde) character. If non of the letters are quoted, then bash will try to treat these letters as a login name. It will then try to replace the tilde expression with the home …

About Brace Expansions This post is based on the documentation of bash brace expansion. Brace expansion is a mechanism that creates strings The basic syntax is: optional preanble (an opening string) a series of comma-separated strings or a sequence expression between a pair of braces optional postscript (a closing …

Shell Operation Covered here in bash documentation. The shell reads its input from one of these: an input from a file from a string supplied as an argument to the -c invocation option from the user’s terminal Breaks the input into words and operators, obeying the quoting rules described in Quoting These words (called …

Create a demo repository Create a new demo repository in github and clone twice: 1cd ../../a/demo/ 2git clone <your demo repository url> 3cd ../../b/demo/ 4git clone <your demo repository url> Create basic feature1 branch (same in both places) Create a feature1 branch in a and add something in it, then push. 1git …