Multi-Platform Probe QUIC Migration: What Changes with PRTG 126 and 128

If you run multi-platform probes, you need to migrate them from NATS to QUIC before you update to PRTG 128. From that version on, NATS connections are no longer supported, and any probe you haven’t migrated loses its connection to the PRTG core server. This post covers the timeline, the migration steps, and the relevant settings. 

In September, we announced that the PRTG Multi-Platform Probe is moving from NATS to QUIC and explained the reasons: simpler onboarding, Ed25519-based authentication with TLS 1.3, and better performance for roaming probes on ships or satellite links. Now, we have committed to the schedule we announced as preliminary back then. 

When does the switch from NATS to QUIC happen?

The switch happens in two stages. With PRTG 126, you can only connect new multi-platform probes via QUIC, and existing NATS probes keep running as before. With PRTG 128, NATS support ends completely, so all existing probes must be migrated first.

The two-stage rollout gives you one full release cycle to migrate your probes without monitoring downtime.

What happens if you don’t migrate before PRTG 128?

Multi-platform probes that still use NATS won't connect to the PRTG core server as soon as you install PRTG 128. No monitoring data from them will reach PRTG until you migrate them to QUIC. To make sure you don’t miss this, PRTG creates ToDo tickets that remind you of the pending migration.

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How do you migrate a multi-platform probe to QUIC?

You migrate a probe by updating it to multi-platform probe 4.x, running the Configuration Wizard, and pasting the new probe access token into PRTG. You don’t need to approve the migrated probe again because the PRTG core server already knows it.

1. On your remote probe system, update your existing probes to the new 4.x version.
2. Run the Configuration Wizard on the remote probe system once the update is complete. The update process prints the command for that.
3. Select QUIC or TCP as the connection type in the wizard.
4. For the CA step of the wizard, Select Fetch it from the PRTG server and verify the certificate thumbprint to use the self-signed server certificate from Paessler, or use a certificate from the system store or a custom path.
5. Copy the probe access token that the wizard creates. It is a string like: "0b5e9c1d-7f3a-4e26-9d84-2c6a1f0e8b37:TXD9G0C2P45BFNABZV9WJS07787E2WQKVAK269DF08D6HXR7A4D0~".
6. In PRTG, go to Setup | System Administration | Probes. Paste the token into Access Tokens under Multi-Platform Probes.

For the exact commands and more details, see the Knowledge Base article How to transfer your multi-platform probes from NATS to QUIC and the Multi-platform probe for PRTG manual.

Which ports does the QUIC connection use?

QUIC uses port 23563/UDP. If you use the TCP fallback, the connection runs on port 23563/TCP instead. The PRTG installer automatically removes the old firewall rules for port 23561, which NATS used. Check that any external firewalls between your probes and the PRTG core server allow the new port.

What if you can’t use QUIC in your network?

If QUIC isn’t an option in your network, use the direct TCP connection with TLS 1.3 encryption. You choose it in the Configuration Wizard, and it offers comparable security. If you used a NATS server to isolate external-facing services in a DMZ, set up a firewall to get the same result. If that doesn’t cover your requirements, contact the Paessler support team. 

Plan your migration now!

Every multi-platform probe that isn’t migrated by PRTG 128 goes offline. Use the time after the PRTG 126 update to move your probes to QUIC, open port 23563, and remove NATS from your setup for good.