How to build one Filesystem on Two Disks

[moser at infbs.uucp]

We will have the following configuration:
 - 4/370 as Server with:
   - 4 1-GByte SMD disks
   - 2 660-MByte SCSI disks
 - diskless clients

Now i'm looking for an idea, how it may be possible to use two physical
drives for one filesystem. I suppose, i need a virtual device driver, but
SUN doesn't have this one (for IPI, it's already done).

Does anybody know, if such a device driver exists.

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