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Rainer Try this explanation.. Host A mounts UFS file system rw Hosts B-C mount sam UFS file system read only In natural scheme of things hosts B-C read files and cache metadata about the files and file system. Host A changes the file system. The metadata that hosts B-C have cached is now incorrect. If they go to access the file system and find that its state has changed things can start to go wrong. Global file systems like QFS have can have one writer and multiple readers as above and the readers can be configured to cache no metadata..or just cache is for a very short time...all is well. Global file systems can also have multiple readers and writers which require more complex mechanisms to maintain consistency. In the case of QFS that requires a server to own the file system metadata and all clients have to get information about the file system metadata from the metadata server. This is done over the network and the transfer the actual data blocks is done over the SAN. HTH Tim Rainer J.H. Brandt said the following : Sorry, this is a bit off-topic, but anyway: Ronald Kuehn writes: --
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