RSCS NJE link to MVS over Basic CTC (Non-SNA)

[Colin Allinson]

I am not sure if anyone can give me any advice on this.

Between our VM systems we use TCPNJE for RSCS links. This leaves us with only a few links to MVS using SNANJE. (Our MVS people expect to have TCPNJE support installed in Q1/Q2 next year).

All terminal traffic to VM is now migrated to TCPIP so VM/VTAM is a **VERY** expensive product for just these few remaining links to MVS.

As an interim measure for the next year we have defined some ESCON CTC links (BCTC) between MVS & VM & are trying to get non-SNA NJE links working.

The link is defined and connects successfully. I can also route traffic over it successfully. However we do see a small but increasing error count on the link.

The problem comes when I close the SNA link so that all the traffic goes over the NJE line in both directions. After a while we get DMTNTR930E message (reason code 0000) denying the request to start stream 1 and a file sits blocking the link until action is taken.

Buffer sizes on both sides are the same (but a bit small at 520). It will take some weeks to get a JES restart on the MVS side to change this.

Is there anything I can do (or any parameters I can change) to make this more reliable - or is it just the nature of the beast?

Colin Allinson
Amadeus Data Processing