‫Hi, and welcome to this lecture
‫on Amazon EFS - Elastic File System.
‫So EFS is a managed NFS, which is a network file system.
‫And because it's a network file system
‫it can be mounted on many C two instances
‫and these EC2 instances can also be
‫in different availability zones.
‫That's the whole power of EFS.
‫So it's highly available,
‫it's very scalable, it's expensive.
‫It's about three times the cost
‫of a gp2 EBS volume and you pay per use.
‫So you don't have to provision capacity in advance.
‫Let me explain.
‫So you have your EFS file system
‫and you surround it with a security group.
‫And then you can have EC2 instances, many of them
‫in the us-east-1a availability zone, for example,
‫or EC2 instances, in the us-east-1b availability zone,
‫or us-east-1c availability zones
‫for your EC2 instances.
‫And they can all connect at the same time
‫to the same network file system through EFS.
‫So the use cases of EFS are content management,
‫web serving, data sharing, WordPress.
‫It uses in internally the NFS protocol.
‫And to control access to your EFS, you need to set
‫up a security group.
‫Now, EFS, it's very important to note that
‫it's only compatible with Linux based AMI and not Windows.
‫You can enable encryption at rest in your EFS drive
‫using KMS, and it's a standard file system on Linux.
‫So uses the POSIX system, and it has a standard file API.
‫And the cool thing about EFS is that you don't need to
‫plan the capacity in advance.
‫The file system will scale automatically
‫and it's pay-per-use for each gigabyte of data
‫you use in EFS.
‫Then we have different performance and storage classes.
‫So the first the scale about EFS, you get thousands of
‫concurrent NFS clients and 10 gigabytes plus
‫of throughputs, and you can grow
‫to a Petabytes-scale network-file system automatically
‫which is really nice.
‫You can also set the Performance Mode at the
‫EFS Network file system creation time,
‫and you have several options.
‫The first one is General Purpose, which is a default.
‫It's used for latency-sensitive use cases
‫such as a web server, a cms, et cetera.
‫But if you wanted to maximize throughput, you have Max I/O
‫which is a high latency kind of network file system,
‫but higher throughput and it's highly parallel.
‫So it's great if you have big data applications
‫or media processing needs.
‫Now, Throughput Mode, you have different options.
‫The first one is Bursting.
‫So you have one terabyte means that it's 15 megabytes
‫per second plus burst up to 100 megabytes per second.
‫So that's the kind of bursting you get.
‫You don't have to remember the numbers,
‫but just to give you an idea.
‫Provisioned is when you want to
‫set your throughput regardless of your storage size.
‫So the previous one was growing in throughputs
‫as we have more storage, but with provisions you
‫can have one gigabyte per second
‫for one terabyte of storage,
‫that is fine because you have de-correlated your throughput
‫from your storage.
‫And finally, to make things a little bit simpler
‫you have Elastic to automatically scale the throughputs
‫up and down based on your workload.
‫So for example, you can get up to three gigabytes
‫per second for reads and one gigabytes
‫per second for writes based on your workload.
‫And this is going to be a great fit when
‫you have unpredictable workloads.
‫Now for storage classes, again multiple options.
‫So you can set up Storage Tiers,
‫and it's a feature to move files
‫to a different tier after a few days.
‫So for example, the standard tier is
‫for frequently accessed files
‫and there is the infrequent access tier, the EFS-IA,
‫which is going to give you a cost to retrieve files
‫if you do ever retrieve them.
‫But when you store these files on EFS-IA,
‫you are paying a lower price.
‫And to enable EFS-IA you must use a lifecycle policy.
‫So let's assume we have some frequently used files
‫on EFS standard, but then one
‫of these files is not accessed for more than 60 days.
‫Then because of the lifecycle policy we set up together
‫the file is going to be moved to EFS-IA
‫in a different tier and it's gonna give us a lower cost.
‫Now in terms of availability and durability
‫you have two options.
‫You can set up EFS to be Multi-AZ
‫which is great for production use cases
‫because if an availability zone is down
‫then it will not affect your EFS file system.
‫But if you want for development to have
‫a one zone EFS file system, you can.
‫So it's great for development, but it's only in One AZ,
‫and backup are enabled by default, and it's still compatible
‫with the infrequent access storage tier.
‫So it's called the EFS One Zone-IA,
‫and that gives you the more aggressive discount
‫which is about 90% in cost saving if you use that.
‫So the example will ask you when should you use EFS
‫and then what options should you set
‫on your EFS network file system to ensure
‫that you validate and comply with the requirements.
‫Okay, that's it for this lecture.
‫I hope you liked it and I will see you in the next lecture.