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Elastic File System (EFS)
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-> AWS EFS lets you create scalable file storage to be used in Ec2 Machines. 

-> EFS we can share with multiple EC2 instances at a time.

-> If we have some configuration files of application and we want to access them in mulitple ec2 instances at a time then we can use EFS concept.


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Step-1 : Create EFS in AWS
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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-07a9a9ac5d5c03420

=> Create 2 EC2 instances (Amazon Linux AMI)

=> Enable security Group inbound rule with "NFS" protocol with 2049 port number.


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Step-2 :  Mount EFS to First EC2 VM
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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-07a9a9ac5d5c03420:/ efsdir

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

# Create a sample text file:
$ sudo touch f1.txt f2.txt

# Run ls command to list the contents of directory.



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Step-2 : Mount EFS to Second EC2 VM
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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-07a9a9ac5d5c03420:/ 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.