CentOS7 simply builds DNS service

1. The function of DNS system in the network is to maintain an address database, which records the corresponding relationship between various host domain names and IP addresses, in order to provide forward or reverse address query services for client programs, that is, forward resolution and reverse resolution.

1. Type of parsing

Forward resolution: reverse resolution of domain names to IP addresses, which is also the longest function: resolution of IP addresses to domain names is not very common, and can be used in some special occasions.

Type of 2.DNS system

1) caching server

Cache data parsed by users to speed up access and save bandwidth resources

2) Principal name server

Save the original data of the DNS area, you can add and delete the data in the modified area

3) from the name server

Also known as the secondary DNS server, the saved copy data of the DNS region can only be read without adding modifications and deleting the zone data, and the primary DNS failure secondary DNS takes over the work.

2. Install and configure DNS

1. Install the DNS configuration master profile

1) yum install DNS

2) filter bind related software after installation

3) modify the main configuration file

4) check whether the DNS main configuration file is incorrect

two。 Configure forward parsing area profile

1) Edit the forward parsing area configuration file

2) add execution permissions, modify owners and groups, and check whether the configuration is incorrect

3. Configure reverse resolution zone profile

1) generate reverse parsing file through forward parsing file

[root@centos01 ~] # cp / var/named/benet.com.zone / var/named/192.168.100.arpa

2) Edit the reverse parsing file

3) check whether the reverse DNS parsing file is incorrect

4) Edit the network card and add DNS

5) restart the network card service, start the DNS server, and set the boot to start automatically

6) use the client to verify that it can be parsed

3. To configure the master-slave replication DNS, you need to start another server as the slave server.

1. Modify the main DNS master configuration file to allow forward and reverse zone data to be copied from the DNS server

two。 Configure data from the DNS master configuration file to the master service

3. Start the DNS service

Systemctl start named

Systemctl enable named