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DNS


How to fix the error “A dns entry for the domain already exists”

"A DNS entry for domain.com already exists, You must remove this DNS entry from all servers in the dns cluster to proceed."

 

Resellers and server owners in cPanel/WHM servers come across this error message when creating domains in their server.

As part of our Outsourced Technical Support for web hosts, we routinely resolve such cPanel/WHM account related errors.

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cPanel DNS cluster – The Pros and the Cons!

A slow website can harm your business as much as a broken site – And you wouldn’t want either of these to happen to you!

That’s where clusters and High Availability setup helps.

As part of our Dedicated Support Services, we configure and maintain High availability clusters for our customers who are web hosts.

A commonly configured one is the cPanel DNS cluster.

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How to secure DNS server

How to secure DNS server

 

DNS is the basis of most internet applications – emails, messengers, web site browsing, etc. But we often tend to miss out the presence of this extensively used service. As a result, server administrators overlook the vulnerabilities in dns service and hackers easily exploit this aspect. (more…)

Reliable, scalable DNS – How DNS clustering and Centralized name servers resulted in fast, scalable and fault tolerant DNS service

The mood was upbeat. It was our weekly business review with a web host we support. Server improvements had resulted in zero service downtimes, and zero customer complaints on service reliability. It was time to figure out how to improve the infrastructure even further, and for that, we looked at the support requests.

Support requests give a gold mine of information on how customers are perceiving the service. Happy customers do not open trouble tickets. So, all support requests are a potential pointer to a system or process improvement. So, we started by looking at the top reasons for support tickets.

Bind Central DNS
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Avoid spamming using anti-spamming DNS records

Avoid spamming using anti-spamming DNS records

Most of us might have come across instances where mails from our domain are marked as spam even though it is legitimate. This article describes few settings that can be implemented in order to decrease the chances of mails originating from your domain being marked as spam.

Spamming can be prevented to a great extend by using anti-spamming DNS records such as SPF, DomainKey and reverse DNS.

SPF :

Sender Policy Framework (SPF) records helps to prevent spoofing of mails by verifying the sender’s IP address. SPF record allows domain owners to specify IP address from which mails will originate, so that receivers verifying the SPF records can reject messages from unauthorized sources before receiving the body of the message.

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An introduction to DNSSEC

In the previous blog, we discussed various DNS vulnerabilities such as Cache Poisoning, Client Flooding, Information Disclosure attacks, Vulnerability in sharing a nameserver and DDos in DNS. DNSSEC provides answers to all except DDoS attacks. DNSSEC is not the abbreviation for DNS security but a set of resource records (such as A record, MX record) which can seamlessly integrate with our existing DNS infrastructure.

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Possible threats to the Internet

DNS is for the Internet, what oxygen is for life. Though we constantly use it, we are unaware of its presence. DNS has come a long way since Stanford Research Institute’s Network Information Center (SRI-NIC) maintained a file called hosts.txt which contained host-names and their corresponding IP addresses, to a complex network of databases called name-servers.

DNS was originally designed to make it easier for us to memorize names (host-names) rather than numbers (IP addresses). Gradually, many applications and protocols used the host-names and IP addresses as a basis to authenticate the host. Thus DNS security came into being, since wrong information from a DNS server, can disallow a legitimate request from a legitimate client.

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Simple Management for BIND

Smbind is a PHP-based software tool for managing DNS zones for BIND via the web interface. This supports the per-user administration of zones, error checking, and a PEAR DB database backend.

 

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Understanding SOA records

Understanding SOA records

I’ve learned that there is nothing more peaceful than a sleeping child – Anonymous, Age 30

To an Internet Administrator, there is nothing more peaceful than a stable and optimized DNS server. The moment there is a wrong configuration, the server wakes up and starts crying, sites and email goes down. An important part of keeping DNS that way is properly setting up the SOA records.

What are DNS Records. DNS records or Zone files are used for mapping URLs to an IPs. Located on servers called the DNS servers, these records are typically the connection of your website with the outside world. Requests for your website are forwarded to your DNS servers and then get pointed to the WebServers that serve the website or to Email servers that handle the incoming email.

 

Hire Bobcares Server Administrators
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Understanding MX records

What is an MX Record

MX stands for Mail Exchange Records. MX records are used in DNS records(or Zone files) to specify how email should be routed.

 

Hire Bobcares Server Administrators
Get super reliable servers and delighted customers

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