mirror of
https://github.com/internetstandards/toolbox-wiki.git
synced 2024-11-22 02:51:36 +01:00
48 lines
2.2 KiB
Markdown
48 lines
2.2 KiB
Markdown
|
This document lists the basic usage of commonly used DNS records. It can be used to track commonly made mistakes.
|
||
|
|
|
||
|
|
# A
|
||
|
|
* Points to an IPv4 address.
|
||
|
|
* Does not point to anyhting else.
|
||
|
|
* Record does not start (left side) with _ or -.
|
||
|
|
|
||
|
|
# AAAA
|
||
|
|
* Points to an IPv6 address.
|
||
|
|
* Does not point to anyhting else.
|
||
|
|
* Record does not start (left side) with _ or -.
|
||
|
|
|
||
|
|
# MX
|
||
|
|
* Points to an A and/or AAAA record.
|
||
|
|
* Preferrably does not point to other record types, but the use of CNAME records is seen in practice. RFC's are inconsistent on this.
|
||
|
|
* Has a priority value.
|
||
|
|
|
||
|
|
# CNAME
|
||
|
|
* Points to other records (A, AAAA, CNAME).
|
||
|
|
* Be carefull with CNAME chaining; don't use too many CNAMEs in a row.
|
||
|
|
* The end of a CNAME chain is always an A an/or AAAA record.
|
||
|
|
* **Can only be combined with NS / SOA records if left side is equal.**
|
||
|
|
|
||
|
|
# SRV
|
||
|
|
* Records starts (left side) with _.
|
||
|
|
* Points to an A and/or AAAA record.
|
||
|
|
* Has a priority value.
|
||
|
|
|
||
|
|
# NS
|
||
|
|
* Points to an A and/or AAAA record.
|
||
|
|
* **Used to point to subzones.**
|
||
|
|
* **Used to indicate what is inside the parent zone.**
|
||
|
|
* **Each zone needs this to indicate what is inside the parent zone as a reference to this zone.**
|
||
|
|
|
||
|
|
# SOA
|
||
|
|
* Mandatory for every DNS zone.
|
||
|
|
* Contains the following information (seperated by a single white space):
|
||
|
|
* FQDN of the primairy name server followed by a trailing dot.
|
||
|
|
* e-mail address of the DNS administrator (followed by a trailing dot, the @ replaced with a dot).
|
||
|
|
* an opening round bracket "(".
|
||
|
|
* serial number that is changed (increased) on every zone change.
|
||
|
|
* refresh time (in seconds) for a secondary name server to check the primairy name server for changes in the zone.
|
||
|
|
* retry time (in seconds) for a secondary name server for requesting the serial number when the primary name server did not respond on the previous request.
|
||
|
|
* expire time (in seconds) after which a secondary name server should stop answering requests if the primary name server is not responding.
|
||
|
|
* Negative caching time to live (in seconds) which is the time a caching name server should cache a negative result (indicating that a name does not exist) coming from the authorative name server before trying again.
|
||
|
|
* a closing round bracket ")".
|
||
|
|
|