DNS named.conf File Explanation

Configuration file:
/etc/named.conf
//And/*//In the named.conf configuration file for comments

The options {/*options option is used to define the environment that affects the entire DNS server, where Di rectory is used to specify the path to the file specified in this file.

Here is the designation to the/var/named, where you can also specify the port and so on. If not specified, the port is 53
*/
Directory "/var/named";
}; //

//
A caching only nameserver config
//
Controls {
inet 127.0.0.1 allow {localhost;} keys {rndckey;};
};
Zone "." In { //The Zone keyword is used in this file to define the domain area, a zone keyword defines a domain area
Type hint;
/* Here are three types of type, they are master,slave and hint respectively, they mean:
Master: Indicates that the primary domain name server is defined
Slave: Indicates that the secondary name server is defined
Hint: represents the root name server in the Internet
*/
File "named.ca"; Used to specify the file that hosts the DNS record specifically
};

Zone "localhost" in {//define a forward zone with a domain name of localhost
Type master;
File "Localhost.zone";
allow-update {none;};
};
Zone "Test.net" in {//Specify a forward zone with a domain name of test.net
Type master;
File "Test.net"
allow-update {none;};
};

Zone "0.0.127.in-addr.arpa" in {//define a reverse domain area with IP 127.0.0.*
Type master;
File "Named.local";
allow-update {none;};
};
Zone "0.192.168.in-addr.arpa" in {//define an IP for 168.192.0.* reverse domain area
Type master;
File "168.192.0";

/var/named/test.net file
@ in SOA dns.wqmsl.com. Root.wqmsl.com. (//SOA means authorization starts
/* Above indicates that the data behind is using Internet standards. The @ represents the corresponding domain name, as it represents Test.net, which represents the beginning of a domain name record definition.

While linux.test.net is the primary domain name server for this domain, Webmaster.test.net is the administrator's email address.

Note that this is the e-mail address used instead of the @ in the common mail address. And SOA represents the beginning of authorization
*/
2003012101; Serial (d. Adams)/* The number in front of the bank indicates the modified version of the configuration file, which is the number of modifications modified on the date of the month,

You should modify this number every time you modify this profile, or your changes will not be updated to the database on other DNS servers on the web.

That is, your updates are likely to not reflect your updates to clients that do not use your configured DNS servers as DNS servers.

It's pointless for them to update you.
*/
28800; Refresh
/* Defines how often a home server is queried from a domain name server to ensure that the data from the server is up-to-date when the refresh rate of the unit is specified
*/
7200; retry
/* The above value is the time interval for retries in seconds, that is, when the service tries to query on the primary server, and the connection fails.

This value specifies how long it will take to try again from the service.
*/
3600000; Expiry
/* Above this is used to specify the number of minutes after which the server clears the corresponding record after the failure to update the primary service.
*/
8400)
/* The above data is used to specify how long the buffer server cannot contact the primary service to clear the corresponding records
*/
In NS WQMSL

In MX ten mail.wqmsl.com.

Linux in A 168.192.0.14
It-test1 in A 168.192.0.133
www in CNAME wqmsl

/* The first column above indicates the name of the host, eliminating the subsequent domain.
NS: Indicates that the host is a domain name server,
A: Defines an A record, which is the corresponding record of the hostname to the IP address
MX defines a message record
CNAME: Defines an alias for the corresponding host

/var/named/168.192.0
@ in SOA dns.wqmsl.com. Root.wqmsl.com. (
1997022700; Serial
28800; Refresh
14400; Retry
3600000; Expire
86400); Minimum
In NS linux.test.net.
/* The meanings of the keywords above are the same as wqmsl.com.
In PTR wqmsl.com.
188 in PTR linux.wqmsl.com.
/*
The first column above represents the host's IP address. The Network Address section is omitted. As 88 complete should be:
168.192.0.88

PTR: Indicates reverse logging
The last column represents the domain name of the host.

DNS named.conf File Explanation