The proper procedure to immediately stop asynchronous replication, including any transfers currently in progress, is to disallow the protection group on the target array. This action instructs the target array to refuse any incoming replication data from the source for that specific protection group. This effectively severs the replication connection and terminates the ongoing data transfer. Disabling the schedule or removing a volume only affects future replication jobs, not one that is already running.

A. Removing the volume member from a protection group: This only stops future replications for that specific volume and does not affect other volumes or an in-progress transfer.

B. Disabling the replication schedule: This prevents future scheduled replications from starting but does not stop a replication job that is already in progress.

1. Pure Storage. (2023). Purity//FA CLI User Guide 6.4. Command: purepgroup disallow. The command description states it is used to "Disallow a protection group on the target array from accepting snapshots from the source array." This action provides an immediate halt.

2. Pure Storage. (2023). FlashArray Asynchronous Replication Configuration & Best Practices. Section: Managing Replication. "To stop replication to a target, you can disable the protection group on the source... To immediately stop an in-progress transfer, you must disallow the protection group on the target array."