Now you can add physical shards as your Azure Cosmos DB for MongoDB (vCore) clusters grow. Thanks to the elasticity of compute and storage configurations in Azure Cosmos DB for MongoDB (vCore), a single physical shard (node) typically delivers the desired performance for most workloads. However, an increasing number of workloads now exceed 32 TiB on a single physical shard or require elevated performance levels that are usually associated with multishard configurations. Additionally, some workloads already hosted on multishard clusters in Azure Cosmos DB for MongoDB (vCore) continue to grow and require additional physical shards.
When you add physical shards, they’re always created next to the other physical shards in the same region and given the same compute and storage configurations as the existing shards in the cluster.
After it’s added, the new physical shard is immediately available for write operations. Often, there is a significant data skew between the existing nodes and the newly added empty shard. To address this imbalance, you can initiate data rebalancing, redistributing data from heavily loaded nodes to those with little or no data. Data rebalancing requires no configuration and is executed with zero cluster downtime.