I'm initializing a XDP relationship from a cluster running ONTAP 9.5P9
The destination cluster is running ONTAP 9.1P16 (Support has confirmed this is a supported relationship)
Source volume is a FlexVol totalling 20TB
The transfer then seems to stop sending/receiving data and the output of "snapmirror show" does not update
Typically I have seen transfers not increment "Total Progress" but "Progress Last Updated" always increments every 15 seconds.
I this situation, both "Total Progress" and "Progress Last Updated" seem to stop incrementing - even though other transfers run with no pausing of progress stats. I can confirm via Grafana (NAbox) that throughput drops to 0 MB/s when this occurs. I have resorted to running a batch script that aborts the transfer and runs the initialize command every hour to keep the ball rolling without constant intervention. This seems to help.
Oh, and by the way... we're pushing this through a 1Gbps LIF until I can get a 10Gbps card installed.