"NO ENTRY AND/OR EXIT POINT" loop

The first check performed by the batch daily planning programs is to ensure that a network has at least a first operation (FOP) and a last operation (LOP).

Suppose you have a plan with the following operations and dependencies:
  • Application A, operation 001, predecessor of B, operation 002
  • Application B, operation 002, predecessor of C, operation 003
  • Application C, operation 003, predecessor of A, operation 001
  • Application D, operation 004, predecessor of E, operation 005
  • Application E, operation 005, LOP
  • Application F, operation 006, predecessor of E, operation 005
Your plan would contain two networks, as shown in Example of a NO ENTRY AND/OR EXIT POINT loop condition.
Figure 1. Example of a NO ENTRY AND/OR EXIT POINT loop condition

The figure shows a plan with two networks, one of which has neither a FOP nor a LOP and therefore is going to generate an entry and/or exit point loop

In this example, network 2 has two first operations (FOP) and one last operation (LOP), which is allowed. Network 1, instead, has neither FOP nor LOP, which means that a loop condition will surely occur. When processing the network, batch daily planning programs detect the loop and issue the message EQQ3150E in the EQQMLOG and EQQLOOP data sets, specifying NO ENTRY AND/OR EXIT POINT as loop type. In the system log, the message EQQ3163E indicates that a loop condition has occurred.