- Now let's take a look at an overview
of all the options we have for storage
within Amazon Web Services.
We have a number of different storage options
in Amazon Web Services,
and let's just start here on the left
with what we call the instance store.
The instance store refers to
block storage that are, essentially what we could say is,
are built in to the EC2 instance.
A number of different EC2 instance types
come with a different type of storage.
It could be a small 30 gig volume,
it could be several terabytes worth of volumes,
and these are, now we say, a free, sort of highlighted here
because the cost of that storage is included
with the price of the machine,
so you're not paying anything additional
to the price of the machine for that storage,
it just comes with it.
Now, these drives within the instance store
are considered ephemeral,
meaning that when that EC2 instance terminates, or stops,
then whatever data is on that particular instance store
will be gone.
And that's because the instance store
is backed by the volumes that are present
on the physical host of that virtual machine.
So, when you stop a virtual machine,
or terminate a virtual machine,
those stores will go away.
Even if you were to stop a machine and start it again,
it's most likely, probably almost even guaranteed
that that instance will come back
on a different physical host
and so that underlining storage subsystem
is no longer available.
And so, that's why we consider the instance store ephemeral.
It's really important to know that
so if that if you have applications
that are writing to that,
then if you lose that machine for whatever reason,
if it fails, if you terminate it,
if auto-scaling pulls that machine back in
and gets rid of it,
then that storage will go away.
We do not have the ability to take snapshots,
so there's no snapshot capabilities of the instance store.
If you want to use that for it's high IOPs capability,
then back ups will be something
that you will have to do on your own.
Now, that brings us to another form of block storage,
which is Amazon EBS, Elastic Block Storage service.
Now, the nice thing about the service is that
these volumes, these disks,
are independent from the machine itself.
Typically what we would do is launch an EC2 instance
and then we would attach an EBS volume to that instance
so that we can have a place to store our data.
But, because this device is independent from the machine,
if we configure things properly,
we could potentially, you know, lose this EC2 instance,
but the data that's on this EBS volume
will still be there
because it's independent from the life of the EC2 instance.
Now, it's important to know that
as far as EBS goes,
what we pay for is a allocated storage per month,
so if we allocate one terabyte for that volume,
but we only use one meg,
we're still paying for the one terabyte
because that's how much we've allocated for the month,
or that's how much we've allocated for that drive.
Now, with EBS volumes we get
a maximum of a 16 terabytes per volume,
and when we say that they're durable,
it means that
the EBS system, inherently behind the scenes will
replicate the data to numerous devices within a cluster
in one availability zone.
So EBS is, to some degree, already redundant
and it's resilient to the loss of a device
within that cluster.
EBS is not resilient to the loss of a data center,
EBS volumes are created per availability zone,
they don't span the entire region.
So, we do have the ability to create snapshots,
and those snapshots are then stored over here in S3.
So, S3 is what we would consider object storage,
and we're gonna talk about the difference between those two
here in just a little bit.
So, with S3 we can get storage,
at least at the time of this video,
storage was somewhere around 3 cents per gig per month.
That's an incredibly low price for storage,
and what we might describe
Amazon's Simple Storage Service as write once, read many,
we might also describe S3 as storage for the internet.
So, we say that because S3 is a really great place
to store things that need to be retrieved
from millions of users out there across the internet.
So we could put images that are meant for a website,
we could put software patches,
PDF documents, videos,
all kinds of things can be stored in S3,
and then we can send our users directly to S3,
bypassing our own systems
and reducing the load on our systems
and just letting S3 handle the delivery
of that content to our users.
It's also important to know that all transfers use HTTP,
that is the protocol for Amazon Simple Storage Service.
Now, the last option that I wanna talk about
with AWS storage options
is what's called the AWS Storage Gateway.
This is a really interesting service in that
ultimately what it is is a virtual machine,
this is published by Amazon Web Services,
and it's designed to be run on-premises,
on an on-premises appliance
using VM wear or Hyper V,
and so you run this in your own
local on-premises data center or co-location, what have you.
And it exposes a device
to which you can use as local storage.
All of the data that is stored there
will be also backed up, encrypted in S3 or Glacier.
You can configure it
to use either one of those services.
If you use S3,
we can use some other mechanisms that we'll talk about,
like life cycle rules to get those files
from S3 to Glacier in another way.
The storage gateway comes in three possible configurations.
One of them that we call the gateway-cached volume,
means that the great majority of your data
is stored directly in S3,
but frequently-accessed data is stored locally,
that's the gateway-cached volume.
The gateway-stored volume
means that we're storing all of our data locally,
but it takes regular point-in-time snapshots
and uploads those snapshots to S3,
and from there, if we wanted to,
we could rebuild those snapshots as EBS volumes
and attach those to virtual machines within EC2.
The last one is what's called a virtual tape library
that exposes an iSCSI interface,
and it essentially looks just like tape,
but that each virtual tape is stored
directly in S3, or Glacier.
So, for those instances where you have
a lot of data on premises
and you have a lot of heavy workload,
you're not ready to move all of that stuff to the Cloud yet,
or perhaps there are things that you
never plan to migrate,
you're gonna leave it back on premises,
but you want a good DR solution,
then the AWS Storage Gateway
is a really good option to consider.
So, those at a high level, those are our storage options
within Amazon Web Services.