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Tech Note: Mirroring with 4D Server v11 SQL
Published On: April 23, 2009
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Mirroring is a way to increase database availability. Database mirroring transfers 4D log files directly from one server to another. In case of failure, the client application can quickly connect to a mirroring server with no loss of committed data. This technology does not require proprietary hardware and is easy to set up and manage. This Tech Note includes a component that facilitates the addition of mirroring to any 4D database.

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Commented by Josh Fletcher on May 17, 2013 at 12:44 PM
WARNING: This Technical Note overlooks one important step when setting up the mirror machine. The journal file must be disabled on the mirror. This is documented in the 4D Server Reference.
Commented by on July 30, 2009 at 7:08 AM
It isn't different. However, it is packaged in a way that allows it to be automated. Running 4D Tools on the source data does break the log, so you need to refresh the data on the mirror whenever compacting or recover by tags is done.

Commented by Joshua Capy on May 1, 2009 at 8:08 AM
How is this different than doing it with the log in 2004? What if tools is run by tags on the primary server will the log still be good on the other server that has not had tools run on it?