A standard DNS A record allows a domain name to be converted into an IP address and is known as a forward mapping. A reverse DNS record does the opposite and allows an IP address to be converted into a hostname.
These reverse records have several names. They are sometimes known as reverse maps, reverse mappings or at other times as PTR records.
These records are not strictly necessary for the server to function. However, many spam email filtering and other security systems check for the existence of reverse DNS records and may be more likely to classify traffic from the server as dubious without a reverse DNS record.
Memset automatically sets a reverse record for every primary IP address. These default records are the same as the default hostname supplied with ever server. For a server with the name examplaaa1 they would be as follows:
examplaaa1.miniserver.com - Miniservers examplaaa1.memset.com - Full Servers
It is possible to modify the default reverse records for all IP address in the account using the the Reverse Map Names page here https://www.memset.com/control/dns/reverse-mapping/ . This page is linked to from the DNS Manager page.
The reverse mapping page contains every IP address that has been allocated to a server in the account along with it's hostname and other information. An example IP address looks like the following:
The columns in the example are as follows:
Server Name This is the designation given to the server by Memset when it was ordered.
Hostname This is the default hostname given to all server's when they are ordered. It is also the default reverse mapping given to the primary IP address.
IP Address The IP that will use the reverse map contained in the last field.
Primary IP? This indicates whether the listed IP is its servers primary IP address. The primary IP of a server will usually be the IP that outgoing connections i.e. sending / relaying emails, will be made on. Therefore, this is the most important IP to set a reverse mapping on.
Reverse Map Name This field contains the hostname that will be set as the reverse map. The drop down list will contain a list of every domain that has been added to the DNS manager of the account. It is not necessary to choose one of these as the field can be edited and any hostname can be entered.
Modifications to the reverse mapping hostnames will not take effect until the Update button is clicked. Please allow 60 minutes for the Memset nameservers to update with the new hostname.
Last updated 10 June 2015, 15:06 GMT