What is my DNS?Your DNS is
What is my User-Agent?
Your User-Agent is CCBot/2.0 (https://commoncrawl.org/faq/).
What is the Domain Name System?
DNS is a system used to convert host names that can grow up to 256 characters to IP. The host name is also known as a fully qualified name and shows both the computer's name and the internet domain where the computer is located. DNS resolves the IP address of a given machine name, allowing machines to communicate with host names on the Internet.
What is the Purpose of Using DNS?
The purpose of DNS is extremely simple, it is easy to understand and provides double-sided conversion between usable machine and domain names and machine IP addresses. Since it is not practical to use and remember IP addresses in daily life, the domain naming system is used. Its main purpose is to respond to inquiries about the domain name or IP number from the network. "Berkeley Internet Name Domain (BIND)" software is widely used for this purpose. When you want to access a site, you can determine which site is located, which IP belongs to which computer, and access it wherever you want.
How it work ?
The DNS system consists of name servers and resolvers. Computers configured as name servers hold the IP address information corresponding to their host name. Resolvers are DNS clients. DNS clients have addresses for the DNS server or servers. When a DNS client wants to find the IP address in response to the name of a computer, the name refers to the server. The name server, the DNS server, if there is such a name in its database, sends the IP address corresponding to that name to the client. Records must be entered manually in the DNS database. Internet addresses are first divided by country. Expressions like tr, de, uk at the end of the addresses indicate the country of the address. For example, en Turkey is also Germany shows uk England. A country name is not used for US addresses because the country that creates DNS and similar applications is the USA. Internet addresses are divided into lower sections such as com, edu, gov after they are divided into countries. These expressions correspond to top-level domains in DNS.
DNS Zone & Record TypesA Record: (Adress Record): It is the address records. Thanks to this record, IP matches are made with host names. These are the records that hold the IP address information of the hostnames.
SRV (Server Record): Records that enable clients to find a server or Domain controller. Clients find the server or Domain controller through this record.
MX (Mail Exchange): It is used to identify an e-mail server. Thanks to this record, the information of the e-mail server is known by DNS.
PTR (Pointer Record): It can only be used in reverse lookup zone. It is the record that matches the name from the IP address.
RT (Route Trough): RT recording is used with X25 and ISDN records. Specifies a host with a specified address, packets directed to a specific Hostname or other devices on the network.
AAA (Adress Record): It does the same with A record, that is, it matches Hostnames with IP addresses, but it is a record designed for use with IP v6.
SOA (Start of Autority): It is the first record in all zones. It is the record that determines that a DNS server is responsible for that zone. That is, it is used to define the parameters of the primary DNS server for a particular zone. Zone version, zone management, data in the zone and name server information are kept in Soa records.
TXT (Text): A record containing descriptive information about a particular resource, such as its location and ownership. It consists of a Text file.
CNAME (Canonical Name): Alias, in other words, determines the path of the record on another DNS server by alias, that is, it allows the record on another DNS server to be recorded in a zone with a different name. However, users cannot see where the host is actually being searched for.
NS (Name Server): Identifies DNS servers on the network that are in use. In other words, it can be said that one dns server can be informed from the other dns server in the network more easily and quickly thanks to this recording.
X25 (X25 Record): Used with Rt record. It is like A record. Unlike A, it matches Hostname with IP address instead of X, as opposed to A record.
ISDN (ISDN Record): It is used with Rt record. The ISDN record is similar to the A and X25 records. Rather than mapping a Hostname from the X25 and A records to an IP address, it matches ISDN addresses.
DNS Zone Files and Record Types;
named.boot: This file is the first file read by the program when DNS starts.
named.local: This file is a file called "loopback" which is used to resolve the address that shows the machine itself.
named.ca: Contains the addresses of the machines on the top level called "root server (.)".
named.hosts: This file is the file where the addresses of the machines in a subdomain running DNS are written, that is, the addresses of all the computers running in your domain are kept.
named.reverse: This file is used to translate the IP addresses contained in the named.hosts file we explained above to the names of the machines and is similar in structure to the named.local file.