A node does not appear, or shows a problem

The node is not on the Nodes tab

Look at the node’s own log (%ProgramData%\Routes\Node\Logs, or /var/log/routes/node):

In the log	Cause	Fix
Central service unreachable	Wrong address, or the port is blocked	Check CentralUrl; Test-NetConnection <central> -Port 5080 from the node.
A certificate error	The node does not trust the central certificate	For a self-signed certificate, give the node its thumbprint (CentralCertificateThumbprints); otherwise the certificate’s name must match the address, and its CA be trusted.
No ApiKey configured / 401	The enrollment key is missing or wrong	Copy it again from Configuration › Node enrollment.
no longer accepts this node’s own key	Its key was reset or revoked, or it lost its data folder	Reset key (or Allow again) on the Nodes tab, so it can enroll again.

The node waits for approval

With New nodes need approval on (the default), a new node appears as Awaiting approval and gets nothing until an administrator approves it on the Nodes tab.

The node shows a problem

Problem	Fix
Cannot listen on port …	Another program uses the port: choose another in Settings, or stop it. On Linux, ports below 1024 need the capability.
Cannot listen for TLS on port …	The node has no usable certificate: see DICOM TLS.
Cannot accept HL7 / DICOMweb …	The same, for the HL7 or DICOMweb port.
Not accepting instances: … GB free	The data volume is below Minimum free disk: see The disk is filling up.
Configuration version … could not be applied	The node keeps its previous configuration; the log says why.

The node is offline

The alert Node … is offline means no heartbeat for the time set on the Alerts tab. Check that the service runs, and that it can reach the central service. A node drained on purpose and stopped does not raise it.