3782586 - no nameserver responding: aborting! err=5500:Failed to send setActive to master. cannot proceed with startup sequence

• An additional host is successfully added to a scale out landscape in HANA as per Adding Hosts to an SAP HANA System
• Post restart of the landscape, the restart fails & the new host's nameserver trace reports a failure to connect with the master nameserver below :
  

  [124995]{-1}[11/-1] 2026-07-15 08:51:40.334541 f TNS              TNSClient.cpp(02950) : no nameserver responding: aborting! err=5500:Failed to send setActive to master. cannot proceed with startup sequence
  
  [124991]{-1}[11/-1] 2026-07-15 08:51:40.334339 e NameServer       TREXNameServer.cpp(10460) : nameserver@hostname:30001 not responding after 10 attempts. giving up
  [124991]{-1}[11/-1] 2026-07-15 08:51:40.334395 e NameServer       TREXNameServer.cpp(04623) : Failed to send setActive to master. cannot proceed with startup sequence
  [124991]{-1}[-1/-1] 2026-07-15 08:51:40.512040 e TrexNet          Channel.cpp(00494) : active channel (since 645457999mues) 10 from 127.0.0.1:40416 to 30001: reading failed with rc=15 (connection broken) 

  
  
• The 'etc/hosts' file on Linux layer and the 'internal_hostname_resolution' on HANA are maintained correctly.
• All servers in the landscape can successfully ping/telnet each other.

SAP HANA Platform Edition 2.0

KBA , HAN-DB , SAP HANA Database , HAN-LM-PLT , SAP HANA Platform Lifecycle Management , HAN-LM-INS-DB , Installation of HANA Database , Problem