Q. What is Melio FS?

A. Melio FS is a cluster file system created by Sanbolic that allows multiple active connections from Windows failover cluster member nodes, as the following diagram shows. Melio FS runs on Windows Server 2003, Windows XP, and Windows 2000, and I’ve run it successfully on Windows Server 2008.

Melio FS isn’t built on NTFS; rather it’s a complete 64-bit file system that’s independent of Windows and allows concurrent read/write to the same volume from multiple nodes. Melio FS takes care of locking, which can be either file-level or, if the application supports it, bit-level, such that different parts of a file can be locked by different applications on different nodes.

Melio FS is completely symmetrical, which means that no host in the cluster controls the file system, and any node can fail and the remaining nodes will maintain uninterrupted connectivity. Melio uses the underlying Windows access control capabilities, so that the same security permissions are available on Melio as on NTFS. You can find more information about Melio FS at http://www.sanbolic.com/melioFS.htm.

Installing Melio FS is simple and consists of a wizard-based install over a few dialog boxes, with no reboot required. After Melio FS is installed on all nodes, you can format a shared LUN with Melio FS using the Melio Format context-menu option in Windows Explorer, as the following screenshot shows.

Make sure the Melio formatted volume has the same drive letter on all nodes in the cluster and that shared storage isn’t a storage resource in a cluster group, since the storage won’t move between nodes because the storage is always available to all cluster nodes.

Check out the following screencast to see how Melio FS works.

Melio FS Demo