XCOM for z/OS retry functionality for TYPE=EXECUTE transfers

Products

• XCOM Data Transport
• XCOM Data Transport - z/OS
• XCOM - SUPPORT
• XCOM Data Transport - Linux PC
• XCOM Data Transport - Windows

Issue/Introduction

Could you please explain how SERL, FERL VERL and TERL are handled differently for EXECUTE and SCHEDULE transfers?

It has been noticed in practice that TYPE=EXECUTE generally fail immediately but we recently had a case where a EXECUTE transfer tried to retry a TCP/IP connection (the listeners were up but the server was not started) with this error message sequence:

XCOMM0126E ... FMH7 SENSE 00000000

XCOMU0469E  ... xcomd is not running or is not compatible

XCOMM0780E Txpi: 215: Socket send error return value = 140

I need clarification of when the TYPE=EXECUTE job will retry and when it won't as this is not documented, whereas the TYPE=SCHEDULE behavior is consistent.

Environment

Release : 12.0

Component : XCOM Data Transport for z/OS

Resolution

• There are limited circumstances in which the TYPE=EXECUTE transfer can retry. We don't have a list of specific situations, but it will honour the SERL=, VERL=, TERL= and as long as the condition is retryable. 
• For the above scenario TCP/IP connection retry (the listeners were up but the server was not started) the fact that XCOM was not active on the remote side can be considered a SERL or TERL type of error and the transfer may retry i.e in that case it was the message XCOMM0745E that triggered the retry.
  
• If you want TYPE=EXECUTE transfers to honour the retries you would have to have a GLOBAL and RESTART dataset in your job. CAI.CBXGJCL(DEFQSAM)

Additional Information

For comparison of TYPE=SCHEDULE and TYPE=EXECUTE see KB article 56208: XCOM TYPE=SCHEDULE and TYPE=EXECUTE