# system.clusters Contains information about clusters available in the config file and the servers in them. Columns: ```text cluster String - Cluster name. shard_num UInt32 - Number of a shard in the cluster, starting from 1. shard_weight UInt32 - Relative weight of a shard when writing data. replica_num UInt32 - Number of a replica in the shard, starting from 1. host_name String - Host name as specified in the config. host_address String - Host's IP address obtained from DNS. port UInt16 - The port used to access the server. user String - The username to use for connecting to the server. ```