3760960 - HANA replication shows unknown state due to replication port conflict (address already in use)

• System replication status for a tenant shows unknown state while performing HANA replication from primary to secondary.
  
  
• This happens after operating system patch update.
  
  
• Index server trace of primary database shows the following error:
  
  Listener cannot be started, because port 42040 is already in use!
  A system replication primary uses replication ports in the range of instance number(s) from 20 to 20
  Please check, that there is no other system on this machine using instancenr 20! This is just a hint and possibly not the root cause ..
  In general the port range 42000-42099 must not be used by any other process when system replication is turned on!
  
  
• Index server trace of secondary database shows error: "local=<ip of secondary>/40644_tcp, remote=<ip of primary>/42040_tcp, state=ConnectWait, pending"

SAP HANA System Replication with Tenant Databases

system replication, unknown state, address already in use, cannot bind to local address, listener cannot be started, port, 42040, port conflict, tcp_established, ip_local_port_range, ip_local_reserved_ports , KBA , HAN-DB-HA , SAP HANA High Availability (System Replication, DR, etc.) , BC-OP-LNX , Linux , Problem