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Elastic File System (EFS)
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-> AWS EFS lets you create scalable file storage to be used on EC2. 

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Some of the EFS advantages are:
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1) Fully managed by AWS
2) Low cost, pay for what you use
3) Highly available & durable service
4) Automatically scale up or down
5) Scalable performance


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Steps to work with EFS
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=> Login into the AWS console
=> Go to Services and select EFS under storage
=> Click on Create file system

File System ID : fs-099b9438a897654a9

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Mounting EFS on EC2
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Before mounting, you need to install the NFS client. If you expand the list and click on “Amazon EC2 mount instructions”, you will get the details.


# Login to EC2 instance and install the NFS client

$ sudo yum install -y amazon-efs-utils

# Let's create a folder where you want to mount the EFS.

$ sudo mkdir efsdir

#  Mount EFS Filesystem (Make sure you changed FileSystem ID)
$ sudo mount -t efs -o tls fs-099b9438a897654a9:/ efsdir

Note: Make EC2 VM security Group inbound rule having "NFS" protocol with 2049 port number

# Change the directory to the mount point that is created above using the command:

$ cd efsdir

# Create a sample text file:

$ sudo touch myfile.txt

# Run ls command to list the contents of directory.

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Note: Create another ec2 instance and mount EFS file system 
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# Login to EC2 instance and install the NFS client

$ sudo yum install -y amazon-efs-utils

# Let's create a folder where you want to mount the EFS.

$ sudo mkdir efsdir

# Mount EFS Filesystem (Make sure you changed FileSystem ID)
$ sudo mount -t efs -o tls fs-099b9438a897654a9:/ efsdir

# Change the directory to the mount point that is created above using the command:

$ cd efsdir

# check the files available

$ ls 

Note : The files we have created in First EC2 instance, should display in second ec2 instance.

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