Windows Server 2008 R2 Unleashed (229 page)

4. When the Diagnostic Report Wizard window opens, select either the health report,

propagation test, or propagation report, and click Next.

5. If a report was selected, the report will be saved to the c:\DFSReports folder with a

default name; if necessary, change the report name and location and click Next.

6. On the Members to Include page, add or remove the desired folder target servers for

the report, and click Next.

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7. On the Options page, select the desired options for the report details, to count or

not count backlogged files and whether or not to count the replicated files and

folders, including data set size on each member, and click Next.

8. Review the selections and if everything looks correct, click Create to generate and

display the report.

9. The report will be displayed in the default browser; close the browser and DFS

Management console when you are finished.

Taking a Target Offline for Maintenance

When a target needs to be rebooted or just taken offline for a short maintenance window,

the connected users must be gracefully referred to another replica, or they must be discon-

nected from the DFS server.

To take a folder target offline for maintenance, follow these steps:

1. Open the DFS Management console and locate the namespace and expand it to

reveal the desired folder and select the folder.

2. Once the folder is selected in the tree pane, in the tasks pane, select the Folder

Targets tab and select the target that will be taken offline.

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3. Right-click the appropriate target, and select Enable or Disable Folder Target, as

shown in Figure 28.27. This option changes the current referral status of a target.

FIGURE 28.27

Disabling DFS referral to free a server for maintenance.

Managing and Troubleshooting DFS

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4. Repeat the preceding steps for any additional DFS root or folder targets on the server

on which you are disabling referrals.

5. Wait long enough for all the existing connections to close. Usually, after you make

the referral change, all users should be disconnected after the cache interval has

been exceeded. Start counting after the referral is disabled. One way to know for sure

that all users have been disconnected from a target is to open Share and Storage

Management on the target server and use the Manage Sessions and Manage Open

Files links in the Actions pane to determine if any users and systems are connected.

6. When all connections are closed on the target server, perform the necessary tasks

and enable the target from the DFS Management console when maintenance is com-

pleted and server functionality has been restored.

Disabling Replication for Extended Downtime

When a server containing a replicated folder target will be offline for an extended period of

time, for upgrades or due to unexpected network downtime, removing that server’s targets

from all replication groups is recommended. Doing this relieves the available replica

servers from having to build and store change orders and staging files for this offline

server. Because the staging folder has a capacity limit, an offline server might cause the

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active server’s staging folders to reach their limit, essentially shutting down all replication.

When the server is once again available, the administrator can add this server back to the

list of targets and configure replication. The data will be moved to the preexisting folder

where it can be compared with file IDs sent over on the change orders from the initial

master. If the file ID is the same, it will be pulled from the preexisting folder instead of

across the WAN to reduce network traffic.

Limiting Connections to Site DFS Targets

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In previous versions of DFS, prior to Windows Server 2003 R2 and Windows Server 2008,

one issue administrators faced was that users could connect to a folder target across a

WAN link for an extended period of time, after only a short network disruption. To

enhance performance and keep this situation down to a minimum, DFS administrators

can set referral priority and restrict folder target access to local Active Directory site DFS

folder target servers. To set referral priority or restrict access to local site target servers,

perform the following steps:

1. Open the DFS Management console, and add the necessary namespace to the console.

2. Expand the namespace to reveal the desired folder, right-click the DFS folder, and

select Properties.

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3. Select the Referrals tab, and check the Exclude Targets Outside of the client’s site and

click OK, as shown in Figure 28.28.

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FIGURE 28.28

Restricting client connections to local Active Directory site for DFS folder

targets.

Backing Up DFS

Administrators do not need to perform any special steps to back up DFS data other than

backing up the actual data in the folders as well as the System State of the servers that

host and participate in the DFS namespace. The following elements should be backed up:

.
Folder Target data—
This is the actual data that is being accessed by end users.

With a true multimaster replication topology, only one target needs to be backed up

for each DFS folder target.

.
DFS hierarchy—
For standalone DFS namespaces, the System State of the root server

and System State of all servers containing DFS targets should be backed up. For

domain-based DFS namespaces, the System States of domain controllers and all

other servers containing DFS targets should be backed up. Active Directory stores all

the DFS hierarchy and DFSR replication connection information. Active Directory is

backed up with the domain controller System State.

To back up the DFS Hierarchy only, the DFSutil can be used to export the settings. To

perform this task, follow these steps:

1. Log on to the Windows Server 2008 R2 system that has the DFS services installed,

with an account with local server administrator privileges.

Using the Volume Shadow Copy Service

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2. Click Start, Run; then type cmd in the search pane and press Enter to open a

Command Prompt window.

3. In the Command Prompt window, type dfsutil domain companyabc.com and press

Enter to list all of the namespaces in the companyabc.com domain as an example.

For our example, we returned the Apps name space located at

\\companyabc.com\apps.

4. Once the namespace name is determined, type dfsutil root export

\\companyabc.com\apps c:\dfs-export-namespace-Apps.xml and press Enter to

export this namespace.

5. In the Command Prompt window, type c:\dfs-export-namespace-Apps.xml to

review the exported information.

This process should be performed on all DFS server and domain-based namespaces for

reference. Also, this file can be used to migrate a DFS namespace from a set of namespace

servers to a different set of servers by deleting the original namespace, editing this file,

and using the dfsutil root import command.

Using the Volume Shadow Copy Service

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The Windows Server 2008 R2 Volume Shadow Copy Service (VSS) is a feature available for

NTFS volumes. VSS is used to perform a point-in-time backup of an entire volume to the

local disk. This backup can be used to quickly restore data that was deleted from the

volume locally or through a network-mapped drive or network file share. VSS is also used

by Windows Server Backup and by compatible third-party backup applications to back up

local and shared NTFS volumes.

VSS can make a point-in-time backup of a volume, including backing up open files. This

entire process is completed in a very short period of time but is powerful enough to be

used to restore an entire volume, if necessary. VSS can be scheduled to automatically back

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up a volume once, twice, or several times a day. This service can be enabled on a volume

that contains DFS targets and standard Windows Server 2008 R2 file shares.

Using VSS and Windows Server Backup

When the Windows Server Backup program runs a backup of a local NTFS volume, VSS is

used by default to create a snapshot or shadow copy of the volume’s current data. This

data is saved to the same or another local volume or disk. The Backup program then uses

the shadow copy to back up data, leaving the disk free to support users and the operating

system. When the backup is complete, the shadow copy is automatically deleted from the

local disk. For more information on VSS and Windows Server Backup, please refer to

Chapters 30 and 31, “Backing Up the Windows Server 2008 R2 Environment” and

“Recovering from a Disaster,” respectively. One important point is that in order for VSS

backups to work properly, shadow copies should be enabled on every volume and enough

free space should exist to store the shadow copies. Even if the schedule is set to once a

year, enabling shadow copies on the volume defines the shadow copies with the Volume

Shadow Copy provider and reduces VSS errors on backups.

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Configuring Shadow Copies

Enabling shadow copies for a volume can be very simple. Administrators have more

options when it comes to recovering lost or deleted data and, in many cases, can entirely

avoid restoring data to disk from a backup tape device or tape library. In addition, select

users can be given the necessary rights to restore files that they’ve accidentally deleted.

The Volume Shadow Copy Service is already installed and is automatically available using

NTFS-formatted volumes.

To enable and configure shadow copies, follow these steps:

1. Log on to the Windows Server 2008 R2 system with an account with administrator

privileges.

2. Click Start, click All Programs, click Administrative Tools, and select Server Manager.

3. In the tree pane, double-click the Storage node, and select Disk Management.

4. In the tasks pane, scroll down to locate the desired volume, right-click the volume,

and select Properties.

5. Select the Shadow Copies tab, and in the Select a Volume section, click on the

desired volume, and click the Settings button.

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6. The Settings page allows you to choose an alternate volume to store the shadow

copies. Select another volume to store the shadow copies in line with best practices

and set the storage space limit for the shadow copies. The default is usually set to

10% of the volume size; accepting the defaults is recommended.

7. After the location and maximum size are configured, click the Schedule button and

define the schedule. The defaults create a shadow copy at 7:00 a.m. and 12:00 p.m.,

but for this example, set up an additional shadow copy to run at 5:00 p.m., as

shown in Figure 28.29.

8. Click OK to close the Schedule window and click OK again to close the Volume

Shadow Copy Settings window. The shadow copy for the originally selected volume

is now enabled.

9. If necessary, select the next volume and enable shadow copying; otherwise, click the

Create Now button to create the initial shadow copy.

10. If necessary, select the next volume and immediately create a shadow copy by click-