MirrorMode
 
Type

Boolean

Default

true

Required

no

Configuration section

[Server]

Description

Run the DIH in Mirror mode.

In Mirror mode the DIH distributes all the index data it receives to all the IDOL servers that it is connected to. The IDOL servers are exact copies of each other which must all be configured in the same way.

You should run the DIH in Mirror mode if you want to ensure uninterrupted service if one of the IDOL servers should fail. While one IDOL server is inoperable, data continues to be indexed into its identical copies which at the same time are still available to return data for queries.

The DIH periodically checks if all the IDOL servers that it connects to are operating. If an IDOL server breaks down, the DIH queues the data that this IDOL server would normally receive, and once the IDOL server starts operating again, it indexes the queued data into it.


Enter false to run the DIH in Non-Mirror mode.

In Non-Mirror mode the DIH distributes the index data it receives evenly across the IDOL servers that it is connected to. For example, if the DIH is connected to 4 IDOL servers, it indexes approximately one quarter of the data into each one of the IDOL servers (individual documents are not split up).

You should run the DIH in Non-mirror mode if the amount of data that you want to index is too large for a single IDOL server. If the IDOL server that the DIH indexes into are situated on different machines, the index process will require less time.

The DIH periodically checks if all the IDOL servers that it connects to are operating. If an IDOL server breaks down, the DIH queues the data that this IDOL server would normally receive, and once the IDOL server starts operating again, it indexes the queued data into it.


IMPORTANT: When you change the MirrorMode configuration option to enable or disable Mirror mode, you must also delete the Main/ subdirectory inside the DIH installation directory. This additional action prevents accidentally switching between Mirror and Non-mirror mode, which can cause a loss of data. If you do not delete the Main/ directory when changing this option, DIH will not start.

Example

MirrorMode=false

See also

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