3680579 - An error "unable to contact primary site.. connection refused" happens while registering DR site

An Error encountered while registering the disaster recovery (DR) system for replication.

[51130]{-1}[-1/-1] 2025-11-09 22:23:00.041314 i Basis            CommandUtil.cpp(00065) : command: hdbnsutil -sr_register --name=SITEC --remoteHost=myhanahost --remoteInstance=00 --replicationMode=async --operationMode=logreplay
[51130]{-1}[-1/-1] 2025-11-09 22:23:00.041494 i Basis            CommandUtil.cpp(00098) : called by user 'ghpadm' with UID: 1001 (parent process command line '-sh ' with PID: 50741) (parent process executable /bin/bash')
..........
    System error: Connect on non-blocking socket failed. rc=111: Connection refused. channel={..............
..............
[51130]{-1}[-1/-1] 2025-11-09 22:23:00.138754 w TrexNet          EndPoint.cpp(00268) : failed to open channel to '127.0.0.1:30001&0': (connection refused)
details: 
[51130]{-1}[-1/-1] 2025-11-09 22:23:00.139022 i sr_nameserver    DRClient.cpp(01547) : entered drRegisterDatacenter with remoteInstance=00; remoteHost=myhanahost; replicationMode=async; name=SITEC; operationMode=logreplay; remoteName=; forceFullReplica=0; verifySubtree=1; useOfflineTopology=0
[51130]{-1}[-1/-1] 2025-11-09 22:23:00.139037 i sr_nameserver    DRClient.cpp(00451) : Remove takeover file: /usr/sap/HAN/SYS/global/hdb/sr_takeover.sem
[51130]{-1}[-1/-1] 2025-11-09 22:23:00.139048 e sr_nameserver    DRClient.cpp(00455) : drRemoveTakeoverPhase() failed: rc=2
[51135]{-1}[-1/-1] 2025-11-09 22:23:00.997031 i Basis            MachineTopology.cpp(00942) : Read initial topology, active logical cores are 0-39 and numa nodes with active cores are 0 and numa nodes with allowed memory are 0 and memory limit is 823543922688
[51130]{-1}[-1/-1] 2025-11-09 22:23:03.143079 w commlib          commlibImpl.cpp(00925) : Connection to 'x.x.x.x:40006' failed: exception  1: no.300015  (Crypto/Shared/SSL/CommonCrypto/Engine.cpp:443) TID: 51130
    SSL certificate validation failed: SSL error [536872221]: Unknown error, General error: 0x2000051d | SAPCRYPTOLIB | SSL_connect
SSL API error
Failed to verify peer certificate. Peer not trusted.
0xa0600203 | SSL_ | ssl3_connect
Peer not trusted
0xa0600203 | SSL_ | ssl3_get_server_certificate
Peer not trusted

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SAP HANA, Platform Edition 2.0

SAP HANA system replication, system replication, register, sr_register, unable to contact primary site, connection refused, SSL certificate validation failed , KBA , HAN-DB-HA , SAP HANA High Availability (System Replication, DR, etc.) , Problem