z/OS change TELNET (TN3270E) port addr

First is to locate the hlq.TCPPARMS (usually SYS1.TCPPARMS or ADCD.Z110.TCPPARMS for ADCD)
It must have the TN3270 member. This is an example:

TelnetGlobals
  INACTIVE 28800
  SMFINIT STD
  SMFTERM STD
  TIMEMARK 14400
  ScanInterval 3600
  MAXRECEIVE  65535
  MAXVTAMSENDQ 50
  TCPIPJOBNAME TCPIP
  ; latest level of VTAM
  TELNETDEVICE 3278-2-E NSX32702 ; 24 line screen -
  TELNETDEVICE 3279-2-E NSX32702 ; 24 line screen -
  TELNETDEVICE 3278-3-E NSX32703 ; 32 line screen -
  TELNETDEVICE 3279-3-E NSX32703 ; 32 line screen -
  TELNETDEVICE 3278-4-E NSX32704 ; 48 line screen -
  TELNETDEVICE 3279-4-E NSX32704 ; 48 line screen -
  TELNETDEVICE 3278-5-E NSX32705 ; 132 column screen-
  TELNETDEVICE 3279-5-E NSX32705 ; 132 column screen -
EndTelnetGlobals

TelnetParms
  Port 23000
    WLMClusterName
      TN3270E
    EndWLMClusterName
EndTelnetParms

BeginVTAM
  Port 23000
  DEFAULTLUS
    SC0TCP01..SC0TCP30
  ENDDEFAULTLUS
; DEFAULTAPPL TSO
  LINEMODEAPPL TSO
  ALLOWAPPL TSO* DISCONNECTABLE
  ALLOWAPPL *
  USSTCP USSN
EndVTAM

We can change the Port on TelnetParms and VTAM.
Once are changed, we must restart the service.

MVS stop TN3270 service: P TN3270

MVS start TN3270 service: S TN3270