The distribution method defines how the DAH distributes actions to its child servers. The behavior of this option depends on whether DAH is in mirror mode or non-mirror mode. In non-mirror mode, the distribution method applies to Distributor VDBs, and to configured mirror groups.
You can configure the distribution method for failover or load balancing:
Failover. In failover mode, the DAH forwards all actions to the first configured child server, or the first configured server that the virtual database maps to. If this server stops responding, the DAH forwards all actions to the next available server. This method provides continued service in the event of a failure.
Load balancing. In mirror mode, when load balancing, DAH uses your LoadBalanceMethod to select the child server to forward actions to. This method distributes the action load between child servers to improve performance.
In non-mirror mode, the DAH performs round robin load balancing between the servers that the distributor virtual database maps to.
There is a third distribution method available if you are using DAH to distribute viewing requests to the View server, where document references are used to request documents.
In this case, you can distribute the actions by reference, so that requests for the same document always go to the same View child server, which makes use of View server caching functionality.
If you use this mode, but do not specify a reference in the action, DAH returns an error.
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