IBM z/OS 2.1 compatibility issue
In Model 204 versions 7.5 and lower, Horizon TCP applications sending data larger than 16K might get the following error:
M204.1254: User language statement is invalid in this conversation state
This error occurs under z/OS version 2.1 because the TCP Default Send Buffer Size (DefaultSndBufSize) was increased to 65536 (from 16384 in earlier versions).
The solutions are as follows:
- Model 204 v7.5:
Apply zap 75Z226.
- Model 204 v7.4:
Currently fixed by zap 74Z4552. Contact Technical Support.
- Model 204 v7.1 (and lower):
Workaround: Set z/OS 2.1 TCP DefaultSndBufSize to 16384.