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Clusters

This article refers to Platform v3.1.0. The current Platform version is v3.2.0.

Overview​

A Docker Swarm cluster is a group of edge nodes that work as a single coordinated system to schedule and run containerized workloads. In Barbara, Swarm is the backbone of HA: clusters give you fault tolerance, scalable orchestration, and consistent configuration across nodes. The Clusters view in Barbara Panel is where you create, list, and monitor them.

Clusters view​

Clusters view

Clusters view

For every cluster the list shows:

  • Cluster Name — the name you assigned to the cluster.
  • Cluster Status — current health (e.g. Healthy).
  • Online — number of nodes currently online.
  • Availability — number of nodes that are active and available.
  • Workloads — count of applications and models deployed on the cluster.
  • Virtual IP — the assigned VIP and whether the feature is enabled.

Per-row quick actions:

  • Edit Cluster — opens the cluster's edit popup.
  • Delete Cluster — removes the cluster.

At the top of the page:

  • Preferences — pick which columns are visible.
  • Search — filter clusters by name or other attributes.
  • + Add Cluster — opens the two-step Add Cluster wizard.

Add Cluster wizard​

The wizard has two steps: Cluster Definition and Node Details.

Step 1 — Cluster Definition​

Add Cluster — Cluster Definition

Add Cluster — Cluster Definition

Fill in the core attributes of the cluster:

  • Cluster name.
  • Enable Cluster Volumes toggle.
  • Enable Virtual IP toggle — when enabled, KeepAlived assigns a floating IP to the cluster.
  • Synctime — a real number greater than 0.005 that controls the cluster sync cadence.
  • Swarm Overlay Networks → Subnet Size — size of the Swarm overlay subnet.
  • Default Address Pool — one or more IP / netmask entries used by the overlay.

The step also exposes advanced settings to fine-tune the network configuration.

Step 2 — Node Details​

Add Cluster — Node Details

Add Cluster — Node Details

Pick the nodes that will join the cluster and configure each one:

  • Advertised Address — the fixed IP address advertised by the node within the cluster.
  • Swarm Traffic Restriction — restrict Swarm traffic to a specific network interface (optional).
  • Node Labels — key-value pairs you can later use for placement constraints during workload deployment.
tip

A minimum of three nodes is the recommended baseline for HA. With fewer nodes you may still have a working Swarm, but you lose quorum and resilience guarantees as soon as one node goes down.

Click Apply to create the cluster. It then appears in the Clusters view.

Summary​

Use the Clusters view to inventory and operate your HA clusters, and the two-step Add Cluster wizard to build new ones. Cluster definition covers the orchestration layer (VIP, sync, overlay network); node details cover the cluster membership and its labels.