$TTL 600 @ IN SOA serverd.lab.example.com. root.example.com. 2025021201 3H 15M 1W 60 IN NS serverb.lab.example.com. IN NS serverc.lab.example.com. servera IN A 192.168.0.10 serverb IN A 192.168.0.11 serverc IN A 192.168.0.12 serverd IN A 192.168.0.13
