For APPC, the sessions are grouped into modesets. Each modeset is defined in the macro method with a TYPE=MODESET macro, and the equivalent in RDO is one SESSIONS definition on the CSD file.
DFHTCT TYPE=SYSTEM,SYSIDNT=ssss,ACCMETH=VTAM,TRMTYPE=LUTYPE62
The parallel sessions for the link are defined collectively by:
DFHTCT TYPE=MODESET,MODENAM=mmmmmmmm,SYSIDNT=ssss,
MAXSESS=(m1,m2)
DEFINE CONNECTION(ssss) ACCESSMETHOD(VTAM) PROTOCOL(APPC)
and a SESSIONS definition from the TYPE=MODESET macro:
DEFINE SESSIONS(xxxxxxx) CONNECTION(ssss) PROTOCOL(APPC)
MAXIMUM(m1,m2) MODENAME(mmmmmmmm)
MODESET1: MAXSESS=4 gives SESSIONS(SYS1AAC) (starting count)
MODESET2: MAXSESS=2 gives SESSIONS(SYS1AAG) (MODESET1 + 4)
MODESET3: MAXSESS=3 gives SESSIONS(SYS1AAI) (MODESET2 + 2)
The MODENAME name mmmmmmmm is the macro MODENAM value.