Stop sending tracking data to another ESP master without stopping ESP STC

Products

• ESP Workload Automation

Issue/Introduction

Have multiple XMITMDL definitions on various MVS nodes as follows: 
XMITMDL ADD MODEL(MODELX) -
NODE(ESP_N1,ESP_N2,ESP_N3,ESP_N4,ESP_N5)

The node where ESP_N5 lived is decommissioned, but the other nodes still have ESP_N5 definition.   This has caused the TP Server checkpoint file filled up (ESPM1456S) on at least one node due to thousands of held transactions for ESP_N5.   The situation is alleviated temporarily by issuing command TPAPPL ESP_N5 DELHELD.

Questions: 
1) What exactly are the held transactions? What generates them? (Jobs are no longer submitted to the decommissioned node.)
2) Is there a command to dynamically remove the connection definition? (TPDISP shows  ESP_N5 (D).)
3) There are nodes which no longer have the ESP_N5 definitions, and ESP has been recycled but command TPAPPL ESP_N5 SHOWHELD still shows held transactions.  How to delete these held transactions? 

Environment

Workload Automation ESP Edition r11.4 & r12.0 

Resolution

Answers:

1.   The held transactions are the job tracking data that could not be sent to ESP_N5.   The following command means that tracking data for jobs tracked by MODELX will be sent to ESP_N5:
             XMITMDL ADD MODEL(MODELX) -
                 NODE(ESP_N1,ESP_N2,ESP_N3,ESP_N4,ESP_N5)

2.  Command to remove definition for the decommissioned node:  
            OPER XMITMDL DELETE NODE(ESP_N5)

3.  Since the held transactions were created BEFORE the connection was removed, use command TPAPPL with DELHELD to manually remove them.