If you want to ensure that FTP has an affinity to a particular TCP/IP stack, use the _BPXK_SETIBMOPT_TRANSPORT environment variable. For more information, see Generic server versus server with affinity for a specific transport provider.
The following example shows how to use the _BPXK_SETIBMOPT_TRANSPORT environment variable to set the FTP server to have an affinity to TCPIPOE:
//FTPD PROC MODULE='FTPD',PARMS=''
//FTPD EXEC PGM=&MODULE,REGION=4096K,TIME=NOLIMIT,
// PARM=('POSIX(ON) ALL31(ON)',
// 'ENVAR("_BPXK_SETIBMOPT_TRANSPORT=TCPIPOE"',
// '"TZ=EST")/&PARMS')