问题
We are working on MarkLogic 9.0.8.2
We are setting up MarkLogic Cluster (3 VMs) on Azure and as per failover design, want to have 3 forests (each for Node) in Azure Blob.
I am done with Setup and when started ingestion, i found that documents are distributed across 3 forests and not stored all in each Forest.
For e.g.
i ingested 30000 records and each forest contains 10000 records.
What i need is to have all forest with 30000 records.
Is there any configuration (at DB or forest level) i need to achieve this?
回答1:
MarkLogic does not work the same as some of the other noSQL document databases failover which may keep a copy of every document on each host.
The clustered nature of MarkLogic distributes the documents across the hosts to provide a balance of availability and resource consumption. For failover protection, you must create additional forests on each host and attach them to your existing forests as replicas. This ensures availability should any 1 of the 3 hosts fail.
Here is a sample forest layout:
Host 1: primary_forest_01 replica_forest_03
Host 2: primary_forest_02 replica_forest_01
Host 3: primary_forest_03 replica_forest_02
The replica forest must be on a different host than the primary forest, and if there are multiple forests per host, they should be striped across hosts to best balance out resource consumption when failed over.
It's also important to note that for HA, you need replicas configured for the system databases as well.
So there is no database setting to put all the documents on every hosts, because that is not the way MarkLogic is designed to work. The Scalability, Availability and Failover Guide is very informative, and in this case, the High Availability of Data Nodes with Failover section is particularly relevant. I also highly recommend checking out the free training that MarkLogic offers.
来源：https://stackoverflow.com/questions/55964039/marklogic-cluster-configure-forest-with-all-documents