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12 SSH interview Q&As

Q1. What is ssh?
A1. SSH is a secure protocol used for remotely connecting to Linux servers. For example, creating an ssh connection from your local laptop to an ec2 instance running on AWS or any server on the cloud.

You will be prompted for a password,

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14 Unix interview Q&As

Q1 How do you remove the Control-M characters from a file?
A1 Using the sed command that replaces Control-M with nothing

Note: The ^M is typed on the command line with ctrl+v and ctrl+M

Q2 How will you search for a property named “inbox”

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5 curl vs wget interview Q&As

Q1. What are the differences between curl & wget? A1. wget is a tool to download files from servers. It let’s you download files from an HTTP/HTTPS or FTP server. You give it a link and it automatically downloads the file where the link points to. … Read more ›...

Hidden Unix, Git & SVN config files

You need to use “ls -la” to list the hidden files in your home (i.e ~) directory. These config files are “.bashrc”, “.inputrc”, “.profile”, etc. In computing, a hidden folder or hidden file is a folder or file that does not display by default when showing a directory/file listing. In Unix-like operating systems,

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sed and awk to write shell scripts for Java developers

Q. How would you go about replacing a piece of a text or a phrase from 20,000+ web templates residing on a Unix file system? Even some candidates with 5+ years of experience will be tempted to spend a day or two to write 200+ lines of code to achieve...

Shell script interview Q&As for Java developers

Q1 How will you go about reading a CSV file as shown below? A1 Q2 How will you read and then write to another file? A2 Q3 How will you read the file and then write to another file with CSV data in different order? … Read more ›...

Top 10 Linux interview Q&As

Many production systems run on Linux systems, especially the Cloud infrastructure (i.e. AWS & GCP). Even Android uses the Linux kernel under the hood. So, it really pays to have a good knowledge of Linux. Q1. How do you check for open ports in Linux? A1. … Read more ›...

Unix history commands for Java developer productivity

When you are using Linux/Unix command line frequently, using the history effectively can be a major productivity boost. You can accomplish things with less typing. For example, you will be typing lots of commands like

and so on. There are 6 ways to repeat your previous commands quickly without having to type a lot.

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Unix remoting interview Q&A for Java developers

Q1 How will you delete files that are older than 7 days in a remote unix server? A1 By ssh ing to the remote host server Q2 How will you copy files from a remote server to a local server? … Read more ›...

Unix sed & awk commands in action

This extends sed and awk to write shell scripts for Java developers. sed & awk are very powerful tool for data engineers to transform text files. Here are a few examples. Q2 Can you explain the following Unix command? A2 The “date” prints the date and time. … Read more...

Unix Sed commands for Java developers

sed (stream editor) is one of the powerful workhorse commands in UNIX. Recently I had to use it with “Git” and “Maven” to find text “SNAPSHOT” in all pom.xml files, and manually update them with a realease version like 1.0.2 without the suffix “SNAPSHOT”.

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Unix shell script to upload & download data between HDFS and edge node

In BigData projects relating to HDFS or AWS S3, it is common to have scripts that transfer or download data from HDFS to the local file system on an edge or gateway node with CLI commands like HDFS, AWS, etc. You also need to upload files from a local file...

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