AWS S3 interview questions

Amazon S3 (Simple Storage Service) is a simple web service interface that allows huge amount of data storage and retrival from anywhere from the internet.Its provides developers highly scalable, reliable, fast and low cost data storage infrastructure.

In S3 bucket you can store unlimited volume of data and number of objects. A single Amazon S3 objects can be a size of range 0 bytes to 5 terabytes. In single upload request You can put an object of around 5 GB but you must have to enable Multipart Upload capability.

use aws s3 ls --recursive command on aws CLI to list all files or objects under the specified directory or prefix

Follow below steps to mount s3 to ec2 instance

1. Update the system

apt-get update

2. Install the dependencies

sudo apt-get install automake autotools-dev fuse g++ git libcurl4-gnutls-dev libfuse-dev libssl-dev libxml2-dev make pkg-config

3. Clone s3fs source code from git

  git clone https://github.com/s3fs-fuse/s3fs-fuse.git

4. Run below commands to change source code directory, compile and install the code.

cd s3fs-fuse
./autogen.sh
./configure --prefix=/usr --with-openssl
make
sudo make install

5. Run s3fs command to check where command is placed

which s3fs

6. Get your access key and secret key ready.

7. Create a new file in /etc with the name passwd-s3fs and paste your access key and secret key.

touch /etc/passwd-s3fs
vim /etc/passwd-s3fs
Your_accesskey:Your_secretkey

8. Change the permission of the file

sudo chmod 640 /etc/passwd-s3fs

9. Now create a directory or provide the path of an existing directory and mount S3bucket in it.

mkdir /mys3bucket
s3fs your_bucketname -o use_cache=/tmp -o allow_other -o uid=1001 -o mp_umask=002 -o multireq_max=5 /mys3bucket

Prerequisite to install AWS CLI.

• Python2 version 2.6.5+ or Python3 version 3.3+

• Windows, Linux, macOS,or Unix

After that, if you are using Unix or Linux system run below command to install AWS CLI

 pip install awscli --upgrade --user

For window and other OS please read: https://docs.aws.amazon.com/cli/latest/userguide/installing.html

You can use invalidations to clear AWS S3 cache. To create invalidations login to AWS Console and go to Distribution Settings > Invalidations > Create Invalidation. Once invalidation is created just type path of file or a wildcard to purge the cache.

Here are steps to delete an S3 bucket:-

• Step1: Login to AWS Management Console.
• Step2: Select S3 from services.
• Step3: Check the bucket you want to delete.
• Step4: Click on the delete button. As confirmation Aws ask you to type the bucket name to delete.
• Step5: Type bucket name and click on the Confirm button.

Versioning allows us to keep multiple variants of an object in a bucket. Versioning helps us to restore an object to a previous or specific version of an object. You can take advantage of versioning to recover a deleted or mistakenly overwritten object.

Versioning helps you to keep multiple versions of an object in one bucket. Here are simple steps to enable versioning on an S3 bucket.

• Step1: Login to your AWS console.
• Step2: From services choose S3.
• Step3: Select a bucket for which you want to enable versioning.
• Step4: Click on the properties tab.
• Step5: Choose versioning from properties.
• Step6: Choose to enable versioning and click on the Ok button.

It is a FUSE filesystem. Amazon web services simple storage service supports it. It can be operated with two different methods

1.Command method-

In this type of mode, s3fs is eligible for managing Amazon s3 buckets in several efficient methods.

2. Mount method-

It is used to mount the Amazon s3 bucket as a local file system.