https://forge.codesys.com/u/pra83/2026-05-02T12:58:05ZRecent posts by pra832026-05-02T12:58:05Z2026-05-02T12:58:05Zpra83https://forge.codesys.com/u/pra83/https://forge.codesys.come8055a4fee59032b550e004f34a29ff61507b3c5

<div class="markdown_content"><p>Hello,</p> <p>We are commissioning an Alarm Monitoring System (AMS) for <br/> a marine vessel and facing a critical issue with CODESYS <br/> SoftRedundancy that we have been unable to resolve despite <br/> extensive troubleshooting.</p> <p>HARDWARE:<br/> 2× HP EliteDesk 800 G9 SFF<br/> Intel Core i7-14700 (20 cores)<br/> 16GB RAM, 512GB NVMe SSD<br/> Windows 11 IoT Enterprise LTSC 2024<br/> NIC1: Built-in Intel GbE<br/> NIC2: Intel I210-T1 PCIe (NIC team)</p> <p>SOFTWARE:<br/> CODESYS Control Win V3 - x64 Version 3.5.22.10<br/> CODESYS SoftRedundancy SL<br/> Server 1 IP: 172.10.10.101 (PLC1 — Active)<br/> Server 2 IP: 172.10.10.102 (PLC2 — Standby)</p> <p>CURRENT CODESYSControl.cfg:<br/> <span>[CmpRedundancy]</span><br/> BootupWaitTime=120000<br/> StandbyWaitTime=12100<br/> SynchronousTimeout=12100</p> <p><span>[CmpSchedule]</span><br/> ProcessorLoad.Maximum=80<br/> WatchdogTime=12000<br/> WatchdogTimeoutAction=0</p> <p>CONFIRMED WORKING:<br/> ✅ PLC1/PLC2 identification configured via IDE<br/> ✅ Connection IP configured via IDE<br/> ✅ AutoSync enabled and written via IDE<br/> ✅ Normal Active/Standby operation working<br/> ✅ Server 2 auto-promotes when Server 1 completely fails<br/> ✅ BootupWaitTime correctly spelled</p> <p>PROBLEM DESCRIPTION:<br/> When NIC1 cable is removed from Server 1 — both servers<br/> go to standalone mode.</p> <p>When NIC1 cable is reconnected — both servers remain in<br/> standalone indefinitely. Neither server auto-recovers to<br/> Active/Standby without manual CODESYS service restart.</p> <p>AutoSync fires (!!! Autosync !!! visible in log) but <br/> recovery does not complete.</p> <p>Tested with direct cable (no NIC team) — same result.<br/> Confirmed not a hardware or NIC teaming issue.</p> <p>KEY LOG MESSAGES:<br/> "Timeout: No sync message RMSG_StartCycle (5) <br/> from master: Standalone"<br/> "Socket on other side closed gracefully 0"<br/> "Standby PLC: Open acyclic work socket failed"<br/> "Connection broke after 11806ms. Check BootupWaitTime."<br/> !!! Autosync !!! (fires but does not complete recovery)</p> <p>PCAP ANALYSIS (Wireshark):<br/> CODESYS sync stops completely at T+3s<br/> Server 1 sends TCP FIN on ports 1206 and 1208 at T+5s<br/> No CODESYS redundancy traffic for remaining 24 seconds<br/> Both servers stay standalone indefinitely</p> <p>WHAT WE HAVE TRIED:<br/> ✅ Corrected BootupWaitTime spelling<br/> ✅ StandbyWaitTime = 12100ms<br/> ✅ SynchronousTimeout = 12100ms<br/> ✅ WatchdogTime = 12000ms (less than StandbyWaitTime)<br/> ✅ AutoSync enabled<br/> ✅ NIC2 set as Standby adapter<br/> ✅ Disabled Windows Network Discovery<br/> ✅ Direct cable test — rules out NIC hardware</p> <p>QUESTION:<br/> Per official CODESYS documentation: "No automatic <br/> Reconnect is included in the functional scope of the <br/> redundancy components. You can program the triggering <br/> of a reconnect."</p> <p>Is RDCY.Synchronize() the correct function to add to<br/> our application for automatic recovery after both PLCs<br/> go standalone?</p> <p>What is preventing auto-recovery when AutoSync is <br/> enabled and PlcIdent is correctly set?</p> <p>Thank you for your support.</p></div>