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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
Enterprise ReplicationThe HCL OneDB™ Enterprise Replication Guide describes the concepts of data replication using HCL® OneDB® Enterprise Replication, including how to design your replication system, as well as administer and manage data replication throughout your enterprise.
Setting up and managing Enterprise ReplicationAfter you design your replication system, you define it and start replication.
Shard cluster setupSharding is a way to horizontally partition a single table across multiple database servers in a shard cluster. Enterprise Replication moves the data from the source server to the appropriate target server as specified by the sharding method. You query a sharded table as if the entire table is on the local server. You do not need to know where the data is. Queries that are performed on one shard server retrieve the relevant data from other servers in a shard cluster. Sharding reduces the index size on each shard server and distributes performance across hardware. You can add shard servers to the shard cluster as your data grows.
Creating a shard clusterTo create a shard cluster, prepare the shard servers and specify the sharding definition.

Creating a shard cluster

To create a shard cluster, prepare the shard servers and specify the sharding definition.

About this task

All shard servers must belong to the same Enterprise Replication domain.

Procedure

To create a shard cluster:

On each shard server, set the SHARD_ID configuration parameter to a positive integer value that is unique in the shard cluster by running the following command:
```
onmode -wf SHARD_ID=unique_positive_integer
```
If the SHARD_ID configuration parameter is already set to a positive integer, you can change the value by editing the onconfig file and then restarting the database server. You can also set the SHARD_MEM configuration parameter to customize the number of memory pools that are used during shard queries.
On the shard server that contains the table to shard, run the cdr define shardCollection command.

What to do next

When applications connect to shard servers, enable sharded queries to run against data across all shard servers by setting the USE_SHARDING session environment variable:

SET ENVIRONMENT USE_SHARDING ON;