DNS Positive Solution zone file
In DNS, we know that there is the concept of domain and region, the English name of the domain is domains, it is a logical concept, and the region English full name zone, it is a physical concept. And zone is divided into positive solution area and inverse solution area.
Positive Solution Area: a service that provides forward parsing, that is, the process of FQDN-->IP
Anti-Solution area: A service that provides reverse resolution, that is, the process of IP-->FQDN
Whether it's a positive or a reverse region, a configuration file is passed, and each entry in the file is a resource record (Resource RECORD,RR).
The types of resource records are primarily these, and the format of these resource records is:
SOA: Start authorization record (start of authority), defines which region the data file was created for
Format:
ZONE_NAME TTL in soa (Primary DNS) fqdn administrator_mailbox (
serial number
Refresh
Retry
Expire
Nagitive TTL)
Description: TTL is a valid length of time that a parse record is saved on a DNS server and can be omitted. If the TTL for each resource record is the same, you can declare it at the top of the file: TTL 600
Remember that the SOA record must be the first resource record entry in the file and can be present in the positive and reverse zone file
The e-mail address here cannot use the @ symbol, which is represented here as the domain name. So the email address is generally written like this:
Admin.xsl.com.
For example: Write a resource record entry for an SOA
Xsl.com. In SOA ns.xsl.com. Admin.xsl.com. (
2014082001
1H
5M
1W
1D)
Note: The units here can be minutes (M), Hours (h), Days (D), Weeks (W), default units are seconds
The Ns:name Server,ns record represents a DNS server within a domain, so its format is this:
Zone_name TTL in NS Ns_fqdn
Ns_fqdn TTL in A IP
Because the NS record is the specified DNS server, who needs to specify the DNS servers in a domain? What is the IP address of this server? Therefore, two records are required.
Here A is a record, the format is the above.
For example: Write an example of an NS record here:
xsl.com. TTL in NS ns1.xsl.com. #这里的域名可以使用 @ means
xsl.com. TTL in NS ns2.xsl.com.
ns1.xsl.com. TTL in A 1.1.1.1 #其实这里的主机名也可以省略, that is, write ns1
ns2.xsl.com. TTL in A 2.2.2.2
The A:address,a record is the process of defining a host (FQDN) to IPv4, which has been stated above and is no longer written here.
However, to illustrate, the A record can only be present in the positive solution region file.
AAAA: This is also a record, but the process of defining the FQDN to IPv6
Mx:mail EXchanger, this is the mail resource record. Because there may be multiple mail servers, we use the priority PRI to determine which mail server to use first. The priority PRI Range is 0-99, the smaller the number the higher the priority
Mail resource record entries are generally defined in the positive solution area file
The format of the mail resource record is roughly the same as the format of the NS resource record:
Zone_name TTL in MX PRI FQDN
FQDN TTL in A IP
For example: Write an example of an MX resource record here:
Xsl.com. In MX ten mail.xsl.com.
Mail.xsl.com. In A 3.3.3.3
Cname:canonical NAME, which is normally present in the positive solution zone file
The format is:
FQDN (new) TTL in CNAME FQDN (old)
For example: Mail.xsl.com. The alias for this host is ml.xsl.com.
Ml.xsl.com in CNAME mail.xsl.com (this is the real name)
Ptr:domain name Pointer , which is a reverse-parsed resource record that can only appear in the Anti-solution zone file.
The format is: Ip.in-addr.arpa TTL in PTR FQDN
For example: 192.168.20.10 's domain name is www.xsl.com., so to write:
10.20.168.192.in-addr.arpa in PTR www.xsl.com.
For example, the hostname with 192.168.20.10 is www.xsl.com. In order to establish a DNS anti-solution zone file
.20.168.192.in-addr.arpa in SOA ns1.xsl.com. Admin.xsl.com. (
2014082101
1H
10M
1D
1D)
10.20.168.192.in-addr.arpa in PTR www.xsl.com.
Just said a region is divided into positive and reverse regions. This is only from the perspective of the query, if the transmission of data from the perspective of the division, then the region type can be divided:
Primary zone: Master, defining the zone of the primary server
From zone: Slave, define the zone from the server
Hint area: Hint, the zone that defines the root domain DNS server
Forwarding zone: ForWord, defining the zone that is forwarded to a DNS server
Where these areas contain positive or inverse regions. Do you understand me?
This article from the "Linux Learning Path" blog, declined reprint!