Hello, Cloud Gurus, and welcome back.
In this lesson, we'll take a look at the traditional method
for distributing data between Windows file servers.
Let's take a look at what we're going to cover.
First up, I'll introduce Distributed File System,
more commonly referred to as DFS.
Then we'll explore DFS namespaces.
We'll also explore DFS replication.
And finally, we'll wrap up with a bit of a demo
of managing Distributed File System.
Now, I know this will be revision for some people,
but it's important to understand for the exam
and you're very likely to encounter DFS on the job.
So let's get started.
Let's take a quick high-level look
at what distributed file system is.
Distributed file system
is a Windows Server storage technology
that enables replication of folder content
between Windows file servers
and the publishing of multiple file shares
using a single name.
And everywhere I've worked throughout my career
working with Windows Server,
I've seen DFS implemented in some way.
So it's important to have a good understanding of DFS
as a hybrid administrator.
There are 2 role services associated with DFS.
The first are DFS namespaces.
This role service provides folder consolidation
into a single namespace
and allows for Active Directory site aware
access to file shares.
And the second role service is DFS replication
and DFS replication provides automatic replication
between folders on separate file servers
and uses intelligent remote differential compression
to efficiently replicate changes between file shares
by only replicating the portion of data that has changed.
What's important to know here
is that you can use these two features together
or independent of each other.
And if you remember back from earlier in the course,
Active Directory makes use of DFS for the /sys/vol folder.
So let's take a closer look at both DFS namespaces
and replication in more detail.
Let's first take a closer look at DFS namespaces.
There are 2 types of namespaces to be aware of.
The first and most common are domain-based namespaces.
This namespace is stored in Active Directory
and on the name servers you specify
and provides high-level redundancy for the namespace
when you have multiple domain controls
and namespace servers deployed.
The domain name is used as the server name portion
of the UNC path.
And the namespace name is used
as the share portion of the namespace.
And a namespace can have multiple targets
and targets are Windows file server shares
that can be accessed via the namespace.
Active Directory sites are used to determine which target
is most likely the best target for the DFS clients.
And by default, when a user accesses
a domain-based namespace, the user is directed
to the most appropriate namespace target
based on their Active Directory site.
You can also have a standalone namespace,
which doesn't require Active Directory.
And instead, the namespace is stored
on a single namespace server,
which may or may not be the server
hosting the actual file shares,
but you'll need to use something like failover clustering
to provide high availability for a standalone namespace.
And a standalone namespace can still have multiple targets,
but you'll most often see domain-based namespaces deployed
and we'll take a look at those in the demo.
Now let's take a closer look at DFS replication.
DFS replication is configured using replication targets.
Replication targets are servers
with a share that have been added to a replication group.
There are 2 replication topologies to be aware of.
The first to be aware of is the hub and spoke topology.
Choose this topology if you have a large number of servers,
or if most of the updates
occur on a specific replication target
and only a few changes occur
at the other replication target
and this topology requires at least 3 servers.
Or you can opt for a full mesh topology
and this is appropriate for 10 or fewer servers
and each server replicates with any other server
and it provides vast replications
where changes are most likely made
on any server in the mesh.
Now, as you would expect,
with multiple locations potentially having files
being created and updated, there may be some conflicts.
DFS uses 2 approaches when dealing with conflicts.
The first is last write wins.
When a file is updated in 2 locations at the same time,
the last written copy of that file is retained
and conflicts are moved to a special hidden
conflict and deleted folder.
And the second rule to remember
is that earliest creator wins.
When a name conflict occurs with two separate files,
the first created file wins
if two files are created at the same time.
And just like you can control replication
between Active Directory sites,
you can control replication between DFS replication targets
with a replication schedule.
All right, let's take a look at a demo
of managing distributed file system.
In this demo, we have 2 Active Directory sites:
the Brisbane site and the Perth site.
And there is also a domain controller in each site
and we have 2 file servers and there's one in each site.
And there's also a file share named Data
that points to our data that we'll use in this demo.
And this share is configured on both of the file servers.
In this demo, we will create a DFS namespace
and configure replication for the share.
And then we will explore the DFS configuration.
And we'll wrap up this demo
by viewing the DFS client configuration.
Let's take a look.
All right, so here I am logged onto an administrative server
and I've gone ahead and installed the DFS namespace
and the DFS replication role services
on our 2 file servers.
And I've also gone ahead and installed the management tools
on this administrative server.
Now I've skipped over this process
because you're fairly familiar with that.
So let's go ahead and start our DFS configuration
by creating a namespace.
I'll minimize PowerShell
and then we'll launch the DFS management console.
So I'll click Start and then Administrative Tools
and then launch DFS management.
We'll get started by creating a namespace,
so I'll right-click Namespaces and select a new namespace.
Now for our first namespace server,
I'm going to use CORP-BNE-FS01.
Go ahead and click Next.
This will just take a moment to validate,
so I'll speed this up and we'll come back when this is done.
Now, I'll go ahead and provide the namespace name.
Now, this will be used as the share name
when users access this share.
I'm going to use the namespace name Global,
but you could pick whatever namespace name
made sense for you.
Then let's have a quick look at the settings
and you can see where it's going to create
this namespace folder
and then what permissions it's going to grant users.
We're okay with these defaults,
so I'm going to go ahead and click OK and then we'll go
Next. We're going to use a domain-based namespace,
but we could create a standalone namespace if we wanted to.
Go ahead and click Next
and then we'll go ahead and hit Create.
Now we can go ahead and click Close.
Now let's go ahead and create a namespace folder.
So we'll just expand out the namespaces
and then expand out the namespace
and then I'll right-click and select a new folder.
We're going to use the name Data
and then we'll add some folder targets in,
one for each of our file servers,
the one in Brisbane and the one in Perth.
So I'll click Add and I'll add in our Brisbane file server.
And that's a share that already exists on that server.
We'll go ahead and click OK.
And now I'll add in our Perth server.
Click OK again and then we can go ahead and click OK again.
Now, it's brought up this fairly handy prompt here
asking me if I want to create a replication group
for the namespace targets that I've just configured.
That's a good idea and we want to do that
so let's go ahead and click Yes
to create our replication group.
This will just take a moment,
so I'll come back when this is done.
All right, now we can go ahead
and configure our replication group.
I'm going to use the same name
for our replication group name
and our replicated folder name.
We'll go ahead and click Next and it's pre-added
our 2 replication folder targets in there,
so we can go ahead and click Next.
We'll make our primary member our Brisbane file server,
so it will be authoritative during initial replication,
so any data on the Perth server will be overwritten
by the data that's on the Brisbane server
if there are conflicts.
We'll go ahead and click Next.
We've only got 2 servers in our replication topology
and changes are likely to be made in both locations,
so we're going to select the full mesh replication topology.
We'll go ahead and click Next.
And you can see that you can control bandwidth if required
and you can set to replicate during specified days and times
if you have low bandwidth requirements
at a particular office.
We're okay to use the full bandwidth
and replicate continuously,
so we'll go ahead and click Next
and then we'll get a bit of a summary
of the settings we've chosen
and I'll go ahead and hit Create.
All right, that replication group has been created,
so I'll go ahead and click Close.
And this is just a reminder indicating that we need to wait
for Active Directory to pick up
all of the replication topology before replication starts.
We're okay with that, so we'll go ahead and click OK,
then let's go ahead and take a look at our namespace,
so we have our namespace
and then we have our namespace folder.
And if I navigate into Replication,
we have our replication group.
And if I just expand this out a bit, we have our 2 servers
that are members of this replication group
and then we have our folder that's replicated.
All right, now let's take a look at a DFS client,
so I'll just open File Explorer
and then we'll navigate to our new DFS namespace folder
and then we'll navigate into our folder target.
And then if I right-click in this white space here
and select Properties to get the properties of this folder
and then select the DFS tab,
we can see that we have access to our 2 folder targets.
And the Brisbane file server is currently our active target
because this administrative server is in the Brisbane site.
But if we were located in the Perth site
or if the Brisbane file server was offline,
then the Perth file server could be our active target.
All right, that concludes this demo.
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?
DFS enables the replication of file shares
and the publishing of file shares using a single name.
And DFS namespaces can be the domain-based or standalone
and domain-based namespaces
provide the highest level of availability and redundancy
by storing namespace data on both the namespace servers
and in the Active Directory database.
And DFS replication can be configured
as either hub and spoke or full mesh topology.
Hub and spoke requires at least three servers
and is designed for scenarios
where data is mostly updated in one location,
whereas the full mesh topology is designed for scenarios
where data is often updated in multiple locations.
All right, that concludes this lesson.
Thanks for being with me and I hope you found it useful,
and I look forward to seeing you on the next lesson.