Good day, Cloud Gurus.
and welcome back for this lesson
where we're going to take a look
at providing high availability for Windows file shares.
Let's take a look at what we're going to cover.
First up, we'll briefly cover off Storage Spaces Direct.
Then, we'll take an introductory look at Storage Replica.
We'll dive into how Storage Replica works.
And we'll also take a look at what's required
to implement and manage Storage Replica.
And we'll wrap up with a demo
of implementing server-to-server Storage Replica.
Let's get started.
Now, I just briefly want to touch on a technology
that allows you to extend the features
of Storage Spaces that we spoke about earlier
in the section to provide redundancy across server nodes
and combine that redundancy potentially with Hyper-V VMs.
Storage Spaces Direct is a storage technology
that allows you to pool together storage
on separate servers and allows you
to run Hyper-V VMs, or host SQL databases.
Each server should have their own local direct
attached storage, and these servers should have
multiple RDMA capable network adapters.
And, as we previously discussed, RDMA allows network traffic
between the servers to bypass the processor,
which boosts performance.
And the servers are then clustered together
to create a storage bus using the pool
of storage across the servers and presenting
that storage as a cluster shared volume,
or CSV, that is accessible from any node in the cluster.
Now, I don't expect that you'll need to know
how to implement Storage Spaces Direct for the AZ-800 exam
as it's specifically listed in the objectives
for the AZ-801 exam, but it is worth mentioning just
for awareness in case Microsoft gets cheeky on this exam.
Now, let's take a look at Storage Replica.
Storage Replica is one of the newer
Windows Server storage technologies.
Storage Replica provides one-way data replication
between server volumes and a Storage Replica partnership
can be configured between two standalone servers,
or between two groups of clustered servers,
or between two or more servers
that are part of a stretched cluster.
Now, the difference between a cluster,
and a stretched cluster is the network latency,
and network latency is typically higher
between physical locations,
or sites than it is within a site.
So a cluster is considered to be within a site
and a stretched cluster is considered
to be between 2 sites.
The replication can be deployed within a site
where there is low network latency between the servers,
or it can be used between sites
where there is higher network latency.
Storage Replica is extremely flexible and powerful.
When you mention the recoverability of a service
you can use terms like recovery time objective,
and that is how long it takes for a service
to available again after failure.
Or you can measure the recovery point objective.
And that is how much data is lost when a failure occurs.
And, depending on how it is configured,
Storage Replica can provide an immediate recovery,
or zero RTO, and provide zero data loss, or zero RPO.
And that's what makes Storage Replica so awesome.
So how does Storage Replica work?
Storage Replica works by performing block-level replication
between the servers in a replication partnership.
And block-level replication means it's incredibly efficient,
only replicating the changed blocks
on the disk between the servers.
Each of the servers in the partnership require
at least two disks in addition to the operating system disk.
The data volume is required for the data to be replicated
and there can be multiple data volumes in a partnership.
And a high speed dedicated log volume
is required for each partnership.
And when you configure a replication partnership
initial replication is performed
between the data volumes in the partnership,
and you can choose to increase the performance
of initial replication by copying
the data using something like removable media.
The replication continues to occur one way
from the primary server to the secondary server
in the partnership until either a failure occurs,
or a manual failover is performed.
And when a failure does occur, failover is only automatic
when you deploy Storage Replica using a stretched cluster.
When you configure Storage Replica
with two standalone servers or two clusters,
both will require manual intervention for failover.
And replication can be either asynchronous
where data is written to the primary server
in the partnership, and then replicated to the partner,
or synchronous where data is written
to the secondary server in the partnership immediately
before the primary server provides the client
with an indication that its write was successful,
and synchronous replication guarantees
no data loss which means it provides
a zero recovery point objective, or RPO.
All right, let's take a look at some of the requirements
for implementing and managing Storage Replica.
And there are quite a few requirements in order
to get Storage Replica up and running,
and the requirements differ slightly depending on
what type of partnership you want to configure.
At a high level, you'll need at least 2 servers
with at least 2 gigabytes of RAM and 2 CPU cores.
And these servers must be in the same domain,
or a trusted domain, and you'll need 5 milliseconds
of latency or less between the partners,
if you want to use synchronous replication.
And just a side note on this, Microsoft guarantees latency
between availability zones to be less
than 2 milliseconds so keep that in mind,
if you're deploying on Azure.
And you'll also need Windows Server 2016 Datacenter or later
and you can use standard edition on 2019 or later,
but it is limited to a single volume,
and at most 2 terabytes in size.
You'll also want decent network adapters on your servers,
preferably RDMA capable adapters,
and the disks must be GPT, definitely not NBR,
and can be configured to use
either the NTFS, or ReFS file system.
And the data and log disks should also match
both sector size, and capacity.
Server-to-server and cluster
to server replication partnerships
can be configured using Windows Admin Center or PowerShell.
Whereas Stretched cluster replication can be configured
using either the Failover Cluster Manager console,
or PowerShell.
All right, let's take a look at a demo of configuring server
-: to-server Storage Replica using Windows Admin Center.
I've deployed 2 servers for this demo
CORP-BNE-SRFFS01 and 02.
And each server has 2 additional disks attached,
a 50 gig disk for data, and a 10 gigabyte disk for logs.
And Microsoft recommends at least 8 gigabytes
for the logs and the bigger the log disk you have,
the more logs your replica servers will store
so they can handle replication failure
for longer periods of time.
And larger or smaller disks do not affect
the performance of the replication.
And using our Windows Admin Center Server
we will install the Storage Replica feature
on each of our servers, and we'll also install
the File Server role, which configures the Windows firewall.
And then we'll configure a replication partnership
using Windows Admin Center.
Let's take a look at the demo.
All right, so here I am logged onto
the Windows Admin Center Server.
We're going to get started by installing Storage Replica.
So I'll just paste a PowerShell command in to install that.
So we're going to install the File Server Role servers,
and the Storage Replica feature on both
of our Storage Replica file servers.
And then, it's going to go ahead and restart those two
servers. So this will just take a moment to install.
So we'll come back when this is done.
All right, that installation is now complete.
And those servers have gone ahead
and restarted in the background.
So I'll go ahead and minimize PowerShell.
Then, let's configure Storage Replica.
To do that, we'll navigate to our first file server.
And then we'll scroll all the way down to Storage Replica.
And implementing Storage Replica
with Windows Admin Center is actually really easy.
So let's quickly step through this process.
We'll select New under Partnerships,
we'll use an existing server or VM and select Next.
We'll type in the first server name in our partnership.
And we'll just provide a replication group name.
And I'm just going to copy the server name,
and indicate that it's between these 2 servers.
Now, our data volume is actually M drive.
And our log volume is actually L drive.
Type in our destination server name.
And we'll just reverse the server names
for the replication group on the other server.
We'll go ahead and select the correct data volume,
and go ahead and select the correct log volume.
And I'll just quickly show you
some of the additional options that are available.
So we're going to use synchronous replication
because these 2 servers are in the same site.
And we can specify our log size.
By default it's 8 gigabytes,
but you could increase that if you wanted to.
And you could also use blocks
that are already seated on the destination server.
For example, if you used a USB drive to copy data
between the 2 servers, you could tick that box.
You can also encrypt the replication traffic.
But, for our purposes, we're okay with these defaults
so we'll go ahead and click Create.
Now, Windows Admin Center uses CredSSP
to configure Storage Replica.
So we're just going to provide the credentials
for our first file server.
Now, it's going to take about 5 minutes
for this partnership to be created,
so we'll come back when that's done.
All right, the replication partnership has been created.
And the initial block copy is being performed
from our first file server to our second file server,
so we'll wait for that to complete and then we'll come back.
All right, the initial replication is now complete.
And we can see that our servers are continuously replicating
between our first file server and our second file server
and that the data volume is M drive.
And if we select this replication partnership
we can see further details
of the replication partnership here
including the log volume and the log size.
And we can even switch the direction
of the replication if required,
or suspend the replication if required.
All right, that concludes this demo.
Now, let's wrap up with a bit of a summary
of what we've covered in this lesson.
All right so what have we covered?
Storage Spaces Direct is a technology
that pools together storage on separate servers
with direct attached storage and allows you
to use that storage to host things
like Hyper-V VMs and SQL databases.
And we also took a look at Storage Replica.
Storage Replica performs one-way replication only
and Storage Replica can only have
a primary and secondary replica.
And you can't have third or fourth replication partners
like you can with something like DFS.
And you should choose synchronous replication
to ensure there is no data loss when using Storage Replica.
And you can use the stretched cluster
Storage Replica deployment option
to limit downtime during a failure.
All right, that concludes this lesson.
Thanks for being with me and I hope you found this useful.
And I look forward to seeing you in the next lesson.