About multi-site single domain with stretched SAN
To configure a multi-site single domain with stretched SAN, the media servers at each site must be configured with SAN access to backup devices at both sites. This access allows media servers to write and duplicate backups between the sites. This configuration works well for distances of up to 50 miles between sites, but becomes less effective as distance and latency increase.
Figure: Multi-site single domain with stretched SAN displays how a replicated global cluster is configured with multi-site single domain with stretched SAN.