>  590     <remote_servers>
>  591         <!-- Test only shard config for testing distributed storage -->
>  592         <test_shard_localhost>
>  593             <!-- Inter-server per-cluster secret for Distributed queries
>  594                  default: no secret (no authentication will be performed)
>  595 
>  596                  If set, then Distributed queries will be validated on shards, so at least:
>  597                  - such cluster should exist on the shard,
>  598                  - such cluster should have the same secret.
>  599 
>  600                  And also (and which is more important), the initial_user will
>  601                  be used as current user for the query.
>  602 
>  603                  Right now the protocol is pretty simple and it only takes into account:
>  604                  - cluster name
>  605                  - query
>  606 
>  607                  Also it will be nice if the following will be implemented:
>  608                  - source hostname (see interserver_http_host), but then it will depends from DNS,
>  609                    it can use IP address instead, but then the you need to get correct on the initiator node.
>  610                  - target hostname / ip address (same notes as for source hostname)
>  611                  - time-based security tokens
>  612             -->
>  613             <!-- <secret></secret> -->
>  614 
>  615             <shard>
>  616                 <!-- Optional. Whether to write data to just one of the replicas. Default: false (write data to all replicas). -->
>  617                 <!-- <internal_replication>false</internal_replication> -->
>  618                 <!-- Optional. Shard weight when writing data. Default: 1. -->
>  619                 <!-- <weight>1</weight> -->
>  620                 <replica>
>  621                     <host>localhost</host>
>  622                     <port>9001</port>
>  623                     <!-- Optional. Priority of the replica for load_balancing. Default: 1 (less value has more priority). -->
>  624                     <!-- <priority>1</priority> -->
>  625                 </replica>
>  626             </shard>
>  627         </test_shard_localhost>
>  628         <test_cluster_two_shards_localhost>
>  629              <shard>
>  630                  <replica>
>  631                      <host>localhost</host>
>  632                      <port>9001</port>
>  633                  </replica>
>  634              </shard>
>  635              <shard>
>  636                  <replica>
>  637                      <host>localhost</host>
>  638                      <port>9001</port>
>  639                  </replica>
>  640              </shard>
>  641         </test_cluster_two_shards_localhost>
>  642         <test_cluster_two_shards>
>  643             <shard>
>  644                 <replica>
>  645                     <host>127.0.0.1</host>
>  646                     <port>9001</port>
>  647                 </replica>
>  648             </shard>
>  649             <shard>
>  650                 <replica>
>  651                     <host>127.0.0.2</host>
>  652                     <port>9001</port>
>  653                 </replica>
>  654             </shard>
>  655         </test_cluster_two_shards>
>  656         <test_cluster_two_shards_internal_replication>
>  657             <shard>
>  658                 <internal_replication>true</internal_replication>
>  659                 <replica>
>  660                     <host>127.0.0.1</host>
>  661                     <port>9001</port>
>  662                 </replica>
>  663             </shard>
>  664             <shard>
>  665                 <internal_replication>true</internal_replication>
>  666                 <replica>
>  667                     <host>127.0.0.2</host>
>  668                     <port>9001</port>
>  669                 </replica>
>  670             </shard>
>  671         </test_cluster_two_shards_internal_replication>
>  672         <test_shard_localhost_secure>
>  673             <shard>
>  674                 <replica>
>  675                     <host>localhost</host>
>  676                     <port>9440</port>
>  677                     <secure>1</secure>
>  678                 </replica>
>  679             </shard>
>  680         </test_shard_localhost_secure>
>  681         <test_unavailable_shard>
>  682             <shard>
>  683                 <replica>
>  684                     <host>localhost</host>
>  685                     <port>9001</port>
>  686                 </replica>
>  687             </shard>
>  688             <shard>
>  689                 <replica>
>  690                     <host>localhost</host>
>  691                     <port>1</port>
>  692                 </replica>
>  693             </shard>
>  694         </test_unavailable_shard>
>  695     </remote_servers>
 

>  82     <tcp_port>9001</tcp_port>