Other DNS Server represent external servers that aren't managed by Address Manager.
You can use external servers when you need to configure DNS delegation, stub zones, and forwarding zones:
- For DNS delegation, the Other DNS Server represents the DNS server that isn't hosting the child zone.
- For a stub zone, the Other DNS Server represents the authoritative primary DNS server.
- For a forwarding zone, the Other DNS Server represents the DNS server hosting the zone to which you will be forwarding queries.
Although it was imported from a Read-Only server, the zone isn't marked as Read-Only because the Other DNS Server doesn't have Read-Only or Read-Write attributes.