ServerBuddies Support Blog

Types of DNS Entries

A
These take names to ips, like www.serverbuddies.com -> 67.228.43.85

PTR
These take ips to a hostname, like 67.228.43.85 -> www.serverbuddies.com

MX
MX records are used by mail servers to look up who to send mail to.

CNAME
This is an alias to another name. Like www.serverbuddies.com CNAME serverbuddies.com

TXT
Text records, these are free form text strings, used for things like SPF records.

NS
These say which servers are authoritative for the domain.

How can I setup secondary DNS server.

1. You can use two of the IP’s assiged to your server.

2. You can setup an additional linux based server and install the free, “DNS Only” version of cPanel.

Latest Installer for DNSONLY servers.

http://layer1.cpanel.net/cpanel-dnsonly-install.sea

This script can also be downloaded as http://httpupdate.cpanel.net/latest-dnsonly

Delivering mail to local mail server if your DNS is hosted on remote Cpanel VSP

Login to WHM and go to “DNS Functions” and select “Edit a DNS Zone”

Select the zone to edit and then select the “Edit” button.

Once the next screen appears scroll down to the “Record Type” MX and change the value to mail.serverbuddies.com.

Change the “Record Type” to “A” for mail and add the IP address of your local mailserver in the box to the right of the “CNAME” record type.

Now DNS server will instruct mail servers on the internet to deliver mail to your local mail server.

Edit the file /etc/localdomains and remove the domain name for which you want email delivered locally.

Edit the file /etc/remotedomains and add the domain name which we removed from /etc/localdomains

Now local (cpanel) mail server (Exim) will route all email originating from the local server to the remote mail server.

Establishing a trust relationship and synchronize DNS records.

We can establish a master/primary nameserver relationship at server setup level. If you do set up a primary nameserver, we need to establish a trust relationship between the two servers so that you can add all DNS entries from the primary nameserver. This saves you having to log on to multiple servers to set up various DNS entries.

To establish a trust relationship with a primary nameserver.

1.Click on the Establish A Trust Relationship With a Primary Nameserver link in the DNS Functions menu.
2.Enter the root password for the trusted nameserver in the Master Server Root Password field.

Once you have established a trust relationship with a primary nameserver, you will need to synchronize the DNS records between the primary and secondary nameservers after you have added new DNS entries.

To synchronize DNS records with the primary nameserver:

1.Click on the Synchronize DNS Records with Primary Nameserver link in the DNS Functions menu.

Specifying the nameserver’s DNS role in WHM

We need to specify which server is to function as a standalone server — that is, a server that only receives DNS data from the other servers in the cluster.

You do not need to link dedicated nameservers to each other.

Under Dns Role, select Standalone next to each web server’s hostname and IP. This will allow the nameserver to receive information from the web server, but not send data to it.

Setting a nameserver to synchronize data to a web server is not recommended, as it will create extraneous zones on the web server.

In most cases, a DNS-only server should never be set to synchronize to a Web server. The Web server should always be set to synchronize to the DNS ONLY server(s), and the DNS ONLY server(s) should always be set as standalone.