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Linux tutorial for Beginners

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Check your current working directory. -> To check the current directory, the command is ‘pwd’. List all the files and directories including hidden files. -> To check the current directory, the command is ‘ls -a’’. Create a nested directory. -> To check the current directory, the command is ‘mkdir -p A/B/C/D/E’’. NOTE - To make a subdirectory or more than 1 folder in a directory, we can run the following command - mkdir -p A/B{/C,/D}/E To view what's written in a file. -> We can use the "cat" command to see the content of a file. To change the access permission of files. -> The command "chmod" is used to change the permission of files which is followed by a numerical number, where 4 = Read, 2 = Write and 1 = Execute. To check which commands you have run till now. -> We use the "history" command to see all the previous commands we have run so far. To remove a directory/folder. -> To delete a directory, we use the "rm -r" c...
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What is DevOps and why it is important?

What is DevOps? It is a methodology, that refers to Development and Operations where people and processes integrate together to form a product and enable the continuous delivery of the products or services to the end users. Automation: It is a process where human input is minimized to speed up production and reduce errors. Scalability: It refers to the automatic increase or decrease of resources or infrastructure according to the need for services. Infrastructure: IT Infrastructure is made up of hardware and software, just an example of a Data Centre, that is hosted remotely, and there, we manage all the hardware stuff, networks, and operating systems with the help of the internet. It’s quite hard to manage the infrastructure manually, a lot of manual effort is required to maintain it. Cost expenditure increased on the failure of the physical memory board, network switches, etc. Nowadays, it’s quite easy to manage the infrastructure with Cloud providers like #Azure, #AWS, and #GCP. We ...
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How DNS server works and the types of DNS server.

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As you type some alphabetic addresses in the URL, what happens next? How did the web browser show you the result? It's all done by Domain Name System. It is like a phonebook for websites, you just have to remember their hostname, no need to remember IP addresses. This is what a DNS does -  Resolve hostname to corresponding IP addresses. It is an Application layer protocol. It uses both UDP and TCP. It works on port number 53. There are 4 types of DNS -  Recursive Resolver (DNS resolver), Root Nameserver, Top-level domain server, and  Authoritative nameserver. 1.   Recursive Resolver - It is the first domain name server. When your device wants to find the IP address associated with the hostname. A DNS query is sent by the DNS client (web browser). Then, the query goes to Recursive Resolver. Recursive resolver operated by ISP (Internet Service Provider), which stores the IP address in its cache. ISP further sends the query to the Root name server if do not find it...
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