Virtualized storage devices for network disk mirroring applications

A computer system, comprising:

• a first server computer including a first non-mirrored storage volume and a first mirrored storage volume;
• a second server computer including a second non-mirrored storage volume and a second mirrored storage volume;
• a communication network connecting said first and second server computers;
• and
• a network operating system implemented within said first and second server computers which supports layered drivers;
• said first server computer including:
• a file system mirror driver for capturing write requests directed to said first mirrored storage volume and transmitting the write requests to said second server computer;
• and
• a state filter driver for examining device commands directed to said first storage volume, determining a device state for the first storage volume, and transmitting said device state to said second server computer;
• and
• said second server computer including:
• a storage device;
• a file system mirror driver for receiving the write requests from said first server computer and directing the write requests to said second mirrored storage volume;
• and
• a state mirror driver for receiving said device state from said first server computer and storing said device state in said storage device.

A mirrored storage system for a clustered computer system, said clustered computer system including a first server computer including a first storage volume;

• a second server computer including a second storage volume;
• a communication network connecting said first and second server computers;
• and a network operating system implemented within said first and second server computers which supports layered drivers;
• said mirrored storage system comprising:
• within said first server computer:
• a file system mirror driver for capturing write requests directed to said first storage volume and transmitting the write requests to said second server computer;
• and
• a state filter driver for examining device commands directed to said first storage volume, determining a device state for the first storage volume, and transmitting said device state to said second server computer;
• within said second server computer:
• a storage device;
• a file system mirror driver for receiving the write requests from said first server computer and directing the write requests to said second storage volume;
• and
• a state mirror driver for receiving said device state from said first server computer and storing said device state in said storage device.

A method for mirroring disk volumes over a networked computer system, said networked computer system including a primary server computer including a primary storage volume;

• a secondary server computer including a secondary storage volume;
• a communication network connecting said primary and secondary server computers;
• and a network operating system implemented within said primary and secondary server computers which supports layered drivers;
• said method comprising the steps of:
• capturing write requests directed to said primary storage volume within said primary server computer and transmitting the write requests to said secondary storage volume within said secondary server computer;
• examining device commands directed to said primary storage volume and transmitting a device state to said secondary server computer;
• and
• storing said device state in a storage device within said secondary server computer.