Transaction Replication Question - how to setup gdk_keep_persisted_log_files?

All, I wanted to have "Transaction Replication" setup for getting an load balanced environment. It's mentioned in the documentation that below property needs to be setup for replication or shipping of the transaction log. How and where should I setup this? Is there anything else I should keep in mind for transaction replication? gdk_keep_persisted_log_files Regards, Sreejith