Requesting checkpointing

When requested, Download for z/OS takes data set checkpoints at specified intervals during transmission of a data set from the z/OS® system to a remote system. At these checkpoints, Download for z/OS requests that both JES and the receiving server record checkpoint data. Checkpointing data enables Download for z/OS to retransmit the data set to the server from the last checkpoint, if a transmission error occurs.

Download for z/OS restarts transmission of a data set from a checkpoint on two occasions:

When a transmission error occurs, and you requested retry in the routing-control data set
When Download for z/OS selects a data set that is previously checkpointed by Download for z/OS