@DanielWhite,
There is a Cloudera Manager command and a YARN job.
- To Abort the command, you can click on the Command Details button under the replication schedule with a running command.
- If the YARN job continues to run, you can kill it like any other YARN job.
Aborting/Killing is safe. The next time you run replication, any files that were already copied will be skipped; any that weren't copied will be copied.