Prevent Data Loss: Local Extent Map Backup on NFS Outages

Customer is requesting a new feature to protect against data loss during shared storage outages, similar to the existing Jira ticket MCOL-5709 which is for S3 failures, but this new feature request would apply to a shared storage (NFS) environment.

To automatically save the latest in-memory extent map to a local disk whenever the system fails writing to the shared storage device helping to prevent significant data loss when shared storage infrastructure fails.