Windows Network Services Architecture series of courses (iv) DNS Advanced technology configuration detailed

1, DNS delegation and sub-zone understanding

In practice, the delegation of DNS and the creation of a child zone play a crucial role.

DNS delegation: In practical application, the creation method is very simple, for example Benet Company is a commercial organization, want to build a own DNS server, and the domain name is benet.com, need to manage the ". com" area of the company application, management ". Only need to be in the corresponding DNS forward lookup zone to add a record of host A, the corresponding IP is benet company DNS public network IP address, and host records can not be benet, otherwise add not up. For example, add a W1 record, the domain name is w1.com, then right-click the. com area, select the zone where the new delegation is delegated to enter "Benet", and then add the IP address of the name server, which is the W1 record you just created (which you can find by "browse"), and then "OK". The Benet company needs to create a "benet. com" Forward lookup zone in its own DNS zone, and then create a different host a record. A record that the client cannot find on the Benet company's DNS can be iterated or recursively queried through "forwarders" or "root hints."

Note: In this case, DNS delegation can reduce the burden of the ". com" domain and avoid the bottlenecks created by the excessive size of the domain name query. All host A records belonging to the zone "benet.com" remain on the Benet company's DNS server. and ". com" area is only a record, such as the client's preferred DNS to fill out the IP address of other DNS servers, when the lookup will be through root hints to the National 13 root DNS servers, and then through the iterative way, the first level down, When the benet.com zone is found, the benet.com zone tells the client the preferred DNS server to search for the delegated benet.com, which is the Benet DNS server, and eventually finds the corresponding host a record.

Sub-zone of DNS: By creating a zone delegation, you can reduce the workload of the DNS server, and if the DNS server zone can satisfy the maximum number of queries for a user, will all host A records be placed in one area? For example, Benet.com region, Benet Company has five branches, the company's internal all users of the host a record in the regional benet.com, if the company has 1000 people, then if one of the machines can not contact DNS, then in the Benet.com area to troubleshoot the fault is difficult, and maintenance is quite Inconvenient. The subregion of DNS can divide a region into multiple subregions and then manage it through the subregion, which also embodies the idea of hierarchical management, and is not based on the idea of creating multiple OUs in a domain?