> ## Documentation Index
> Fetch the complete documentation index at: https://docs.abbyy.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Set up a distributed file system
> Make ABBYY FlexiCapture Processing Server file storage fail-safe with DFS Namespaces and DFS Replication, covering roles, shared folders, and namespaces.
When installed on a cluster, the Processing Server uses file storage to store temporary files. If the file storage fails, the entire cluster will go down. To ensure continuous operation of the cluster, you need to make your file storage fail-safe.
For the [file storage](/flexi-capture/admin-guide/architecture-ag) that will store document images and captured data, you need to use hardware solutions (for example, RAID disks). Software-based distributed storage solutions are not supported.
This topic describes one possible implementation of fail-safe file storage using DFS Namespaces and DFS Replication. DFS Namespaces creates a virtual directory of multiple folders located on different servers, which will remain accessible even if one of the servers fails. DFS Replication automatically tracks changes in the `ServerSettings.xml` files and replicates them in a backup folder.
In the following instructions, a computer named `DCsrv` is used as the host server, but you can use any computer where the DFS roles are set up.
Before you begin, you will need:
* A computer running Windows Server 2012 or later that is not used as a cluster node or for file storage
* The DFS Namespaces and DFS Replication roles set up on that computer
* The DFS Namespaces and DFS Replication roles set up on all of the nodes
* A shared folder, with full control permissions for the `node1admin` and `node2admin` users, that serves as a backup when the main shared folder becomes inaccessible
To set up a distributed file system, complete the following steps:
1. [Add the DFS roles](#dfs-roles).
2. [Create shared folders](#dfs-file-share).
3. [Create a namespace](#dfs-namespace).
4. [Add the shared folders to the namespace](#dfs-adding-file-shares-to-namaspace).
5. [Set up replication](#dfs-replication).
6. [Set up priorities for the folder targets](#dfs-priority).
7. [Configure the ABBYY FlexiCapture Processing Server service](#dfs-setting-fcprocessingserver).
## Add the DFS roles
1. Open **Server Manager** and click **Add Roles and Features**.
2. At the **Select server roles** stage, expand **File and Storage Services** and select **DFS Namespaces** and **DFS Replication**.
## Create shared folders
The shared folder must:
* Be used only to replicate data from the cluster.
* Not be located on a cluster node or in the file storage.
* Be accessible to all nodes.
To create the shared folder, open **Server Manager**, click **File and Storage Services → Shares**, and then click **Tasks → New Share...**. Next, complete steps 2 through 14 described in [Create a shared folder for the Processing Server service](/flexi-capture/admin-guide/fail-safety-proc#network-folder).
## Create a namespace
Namespaces are created and configured in the **DFS Management** console, where you select a server, grant access permissions to users, and specify the namespace type.
1. Open **Server Manager** and click **Tools → DFS Management**. In the DFS Management snap-in that opens, click **New Namespace...**.
2. Specify the name of the server that will host the namespace and click **Next**.
3. Specify a name for the namespace and click **Edit Settings...**.
4. In the **Edit Settings** dialog box, select the **Use custom permissions** option and click **Customize...**. Next, grant full control permissions for the shared folder to the `node1admin` and `node2admin` users.
5. At the **Namespace Type** stage, select **Domain-based namespace**, and then select the **Enable Windows Server 2008 mode** option and click **Next**.
6. Check to make sure that the specified settings are correct and click **Create**.
7. Click **Close** to close the wizard.
## Add the shared folders to the namespace
Add the main and backup shared folders to the namespace:
1. In the DFS Management snap-in, click **New Folder...**.
2. In the dialog box that opens, specify a name for the folder, and then click **Add...**. The name will be displayed in the namespace of the distributed file system.
The name you provide for the shared folder must not be the same as the name of any replicated folders.
3. Specify the path to the shared folder and click **OK**.
4. Click **Add...** again and specify the path to the backup folder. Both folder targets appear in the **Folder targets** list. When you are done, click **OK**.
5. A message will appear saying that you can create a replication group. Click **Yes** to create a replication group and start setting up replication.
## Set up replication
Setting up replication means creating a replication group, specifying a server, selecting a topology of connections among group members, choosing a replication schedule, and specifying replication bandwidth. You configure all of this in the **Replicate Folder Wizard**:
1. The wizard will suggest the names of the replication group and replicated folder. Edit these names if necessary or keep the default names and click **Next**.
2. The wizard will inform you if the folder targets can participate in replication. Review the information in the **Eligibility** column and click **Next**.
3. Select the server that contains the data to be replicated to folder targets and click **Next**.
4. For the topology to be used, select **Full mesh** and click **Next**.
5. For the replication schedule, select **Replicate continuously using the specified bandwidth**. From the **Bandwidth** drop-down list, select **Full** and click **Next**.
6. Check to make sure that the specified settings are correct and click **Create**.
7. Once the replication group is created, click **Close** to close the wizard.
8. If a **Replication Delay** warning appears, click **OK**.
After you have set up replication, we recommend testing it to make sure that it works correctly. To do this, open the **DFS Management** snap-in, select the newly created replication group, and click **Create Diagnostic Report**:
In the **Diagnostic Report Wizard** that opens, select the **Propagation test** option and follow the instructions of the wizard (we recommend keeping the default settings).
Once the diagnostic is complete, the **Diagnostic Report Wizard** will display a diagnostic report.
## Set up priorities for the folder targets
To minimize the risk of malfunction, we recommend setting up priorities for the folder targets.
This is one possible priority setup for the folder targets. Other setups are possible, depending on your needs. For detailed instructions on setting up target priorities, see [this page on the Microsoft website](https://docs.microsoft.com/en-us/windows-server/storage/dfs-namespaces/set-target-priority-to-override-referral-ordering).
1. Open your namespace and then open the properties of the shared folder.
2. Click **Advanced**, select the **Override referral ordering** option, and then select **First among all targets**. This option means that users are always directed to the selected folder target when it is accessible.
## Configure the ABBYY FlexiCapture Processing Server service
To keep the cluster hosting the ABBYY FlexiCapture Processing Server service running even if the file storage fails, complete these steps.
If the file storage fails, the data about the sessions that are open at the time of failure may be lost.
1. Complete steps 1 through 4 described in [Set up the ABBYY FlexiCapture Processing Server service](/flexi-capture/admin-guide/fail-safety-proc#procserv-local-setup), but in step 1, change the path to the file that contains the Processing Server settings. The command in step 1 should be as follows:
```
sc config ABBYY.ProcServer.FlexiCapture.12.0 binpath= "%systemdrive%\Program Files\ABBYY FlexiCapture 12 Servers\FlexiBRSvc.exe \service -stationType:server -inifile:\\cluster2016.com\DFS\FC12ClusterTemp\serversettings.xml"
```
Copying and pasting the above command may introduce redundant new line characters, resulting in an error. If this is the case, type the command manually.
2. Change the `%appdata%` variable directly in the Windows registry to `\\cluster2016.com\DFS\FC12ClusterTemp` (see [Change the %appdata% variable](/flexi-capture/admin-guide/fail-safety-proc#appdata-changing)).