When enabled, all vSphere API calls made by this cloud share one long-lived session instead of performing a full login → operation → logout cycle for every individual request (clone, power-on, snapshot revert, delete, …). This eliminates dozens of redundant authentication round-trips per agent lifecycle, reducing load on the vCenter and speeding up provisioning.

The shared session is created on the first request and kept alive in the background according to the health-check, age, use-count, and idle-timeout settings below. If the session expires unexpectedly (e.g. the vCenter was restarted) the pool reconnects automatically on the next request.

Leave disabled if you prefer the original stateless behaviour (a fresh login per operation), for example when multiple Jenkins controllers share the same vCenter account with a strict concurrent-session limit.

Saving this cloud's configuration (from the UI or via JCasC reload) always replaces it with a fresh pool using the new settings; the previous pool - and any session it still holds open - is logged out shortly afterwards. All pooled sessions are also logged out when Jenkins itself shuts down.

Configuration via JCasC (Configuration as Code)

Add the following keys under the vSphere cloud entry in your jenkins.yaml. Only useConnectionPool: true is required; the remaining keys default to 0 (feature disabled).

jenkins:
  clouds:
    - vSphere:
        vsDescription: "My vCenter"
        vsConnectionConfig:
          vsHost: "https://vcenter.example.com"
          credentialsId: "vcenter-creds"
        instanceCap: 20
        maxOnlineSlaves: 0

        # --- Connection pool settings ---
        useConnectionPool: true

        # Re-check session health every 60 seconds (0 = disabled)
        poolHealthCheckIntervalSecs: 60

        # Restart the session after 1 hour regardless of activity (0 = never)
        sessionMaxAgeSecs: 3600

        # Restart after 500 uses (0 = never)
        sessionMaxUses: 500

        # Disconnect after 5 minutes of no activity (0 = keep alive forever)
        poolIdleTimeoutSecs: 300

        templates:
          - ...