Hi,
This issue is mentioned in this KB. However, only the EMS logs will reveal if this is an exact issue.
Snapvault (XDP) failed with Error Volume access error(Permission denied):
https://kb.netapp.com/app/answers/answer_view/a_id/1085558/loc/en_US#__highlight
Cause:
This issue might occur if SnapVault transfers are carried out when both the source and destination volumes experience heavy NFS traffic.
Solution
Manual update of XDP relationships using the command:
# snapmirror update -destination-path <vserver_name>:<volume_name>
Check if you see any errors similar to the one mentioned in the kB:
::*> event log show -message-name wafl.repl.send.inode.err*
Try updating after some time, in the mean time check the NFS traffic IOPS/MBPS.
If you have OCUM/AUM, you can easily narrow down how the traffic's been for the volume concerend.
Thanks!