In my previous post, we’ve seen how we can configure shared configuration for multiple IIS servers in a farm. We used a shared folder on one of the servers to save the configuration, and pointed the rest of the IIS servers to that folder.
The problem with this approach is that, if the server on which the shared folder resides goes down, the rest of the IIS servers will go down as well, since they will loose access to the configuration files.
There are multiple ways to tackle this issue, the most common being putting the configuration files on a highly available storage device, like a SAN. While this solves the problem, it adds costs and complexity to the farm.
Another solution is to make use of a Windows feature called Offline Files. Offline Files allows you to have the content of a UNC share available even if the share is not accessible.
To enable offline files on Windows Server 2008 R2, you have to do the following
First thing that needs to be done is to install the Desktop Experience feature
1. Open the Server Manager, click on Features, and then click on Add Features
2. Select Desktop Experience from the list of features, and then click Next. If it asks to add required features, click the Add Required Features button.
3. Click the Install button on the next screen.
4. After the install process finishes, restart the server.
5. After the server starts, open the control panel, and search for offline.
6. Click on Manage Offline Files. A window will open as seen below
7. Click on Enable Offline files button, and then click on the Ok button. The server will have to restart.
8. One the server restarts, open Windows Explorer and browse to the server hosting the shared folder.
9. Right click on the shared folder and click on Always available offline
10. Open the Control Panel if its not open and search for offline.
11. Click on Sync Center. In the window that opens, select Offline Files
12. Click on Schedule.
13. Choose the shared configuration folder that we just made available offline and click next.
14. In the next screen, choose the At a scheduled time option
15. In the next screen, choose the interval with which you want the sync to happen. It can go down to minutes if required. Click the Next button
16. Give a name to the schedule and then click Save schedule button.
After completing the above steps, you will have a shared folder that is available even if the host server goes down. This will give you some time to recover the failed server without bringing the whole farm down.