Server
A server is a machine that runs Clustron Zaris. It hosts the management service on port 7801, and in supervisor mode it forks and owns the node processes that live on that machine.
What a server is
A server is a physical or virtual machine, identified by its host and management port — for example machine-d:7801. It runs the Zaris management service, which is the machine's point of administration. This management service is also called the manager; it forms the control plane and stays off the request path, so administrative work on a server never stalls a data operation on a node.
A server listens on management port 7801 by default. That is the address you record in a workspace and the address New-ZrStore, Add-ZrServer, and the console talk to.
Supervisor mode: a server owns its nodes
In supervisor mode a server does more than answer administrative calls — it runs the nodes on its own machine. When you create a store, the server forks the node processes for its share of the layout, writes their configuration, and starts and stops them. Each node it owns gets a client port from 7861 up and a cluster port from 7811 up, incremented per node on the machine.
The number of node processes a server runs for a store is partitions per node × replication factor. Because a server owns whole node processes, a single machine can host a realistic multi-node cluster for development.
In attach mode the model differs: the nodes run under an orchestrator such as Docker Compose or Kubernetes, and the server's manager only observes them rather than forking them. See Deployment models.
The server is the unit of scaling
In supervisor mode you grow and shrink a cluster a server at a time, never an individual node. Add-ZrServer claims a blank, reachable server into the workspace and makes it run the same homogeneous share of every store the other servers run; the partition map then expands and redistributes automatically. Remove-ZrServer is the reverse.
# Add machine-d to the active workspace; every store grows onto it and partitions rebalance
Add-ZrServer -Address machine-d:7801
Adding a server extends each store's canonical definition with the new server's node layout, propagates that definition to every server so the configuration stays consistent across the workspace, forks and starts the new server's nodes, then appends the server to the workspace roster.
How a server relates to the other terms
A server is a machine; the other building blocks are logical. A workspace is a client-side list of servers' management addresses. A cluster is the set of nodes the servers run for a store. A node is one process a server forks and owns. A store is the data those nodes present. So one server can host nodes for several stores at once, and one store's nodes can be spread across several servers.