First, the role of the DNS system in the network is to maintain an address database, which records the various correspondence between domain names and IP address of the host in order to provide a forward or reverse address lookup services to clients, namely being analytical and counter parsing the
type of Resolving
- Forward Analysis: the domain name into an IP address, the longest useful features
- Reverse lookup: resolves IP addresses to domain names, is not very common, will be used on special occasions
type of system 2.DNS
1) cache server
caches the user parsed data, speed up access speed, saving bandwidth resources
2) the name of the main server
to save the original DNS zone data, you can add amendments to delete the data area
3) from the name server
is also known as a secondary DNS server, copy the data stored in the DNS zone can not be added to modify the deleted area data can only be read, the primary DNS secondary DNS failure takes over
two, installation configuration DNS
1. DNS configuration master installation configuration file
1) yum install DNS
filtered bind 2) after installation software
3) modify the main configuration file
4) whether an error check of the primary DNS configuration file
configuration forward resolution area profile
1) forward resolution region profile edit
2) execute permission, to modify the owner and group check whether the configuration error
configuration reverse DNS zone profile
1) parse the file generated by forward reverse lookup file
[centos01 the root @ ~] /var/named/benet.com.zone /var/named/192.168.100.arpa CP #
2) reverse lookup file editing
3) Check the reverse DNS resolution file error
4) editing card, add DNS
5) Restart card services, start the DNS server settings at startup
6) using the client to verify that you can resolve
three replicate master-slave configuration DNS, you need to turn on a server as a slave server,
1. Modify profile allows the master copy of the primary DNS forward and reverse DNS zone data from the server
2. The service configuration to the master data from the master configuration file DNS
3. Start the DNS service
systemctl Start the named
systemctl enable the named