You can control the number of intermediate nodes through which a job (or SYSOUT) will be routed before JES2 determines that the data is looping in the network. The MAXHOP= parameter on the NJEDEF statement specifies the maximum number of nodes (0-65535) through which a job can travel before it is placed in hold. This parameter applies only to jobs arriving at this node from another node, not to jobs submitted locally.

JES2 begins the node count when the job is submitted and continues incrementing the count until the job prints. An installation can reset the count through both the $R and the $T O commands. To understand how to reset the count and alter the characteristics of output routed across a network, see z/OS JES2 Commands.

Specify a MAXHOP= value greater than twice the number of nodes in the longest path in your network. This allows for a job to traverse the network and output to return, plus an additional allowance if necessary for alternate path routing. If you do not specify a value for MAXHOP=, the default value is 0. This parameter does not count traffic travelling through intermediate nodes in the network.