An A record is a type of DNS record that maps a name to an IP address. For example, the A record for serverfault.com is 64.34.119.12
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A Record VS. Cname Round N
Experienced DNS Admins please help me understand...
I run a small DNS server in a development environment that runs resolution for at most 5 domain names at any one time. My question stems from a ...
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www a-record vs cname-record
I have a website that I will be hosting the DNS for (testing purposes at first and then it will have some limited traffic).
I have set up DNS so that site.tld has an A record to the actual IP, but I ...
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Why are Amazon EC2 Elastic IPs encouraged to be used with a CNAME rather than an “A” record?
I am setting up a server on EC2 that will be used by people that will be freaked out when they see ec2-111-111-111-111.compute-1.amazonaws.com in the URL bar. I know this would be solved by using an ...
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4answers
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should Apex domains (and records) be avoided?
I'm building an app that is hosted on Heroku. Heroku suggests that Apex Domains are a Very Bad Idea -- they suggest using CNAME records and a workaround service like Zerigo or DNSSimple. However, ...
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CNAME and A record have different TTLs. Which one will be cached?
If a CNAME has a TTL of 1 hour that points to an A record with a TTL of 1 minute, will someone who looks up this CNAME have the entire result cached for 1 hour, or will it will keep having to lookup ...
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Best practice for placing DNS records and subdomains
Say I have mydomain.com:
Is it better to use option A:
[A] mydomain.com 123.45.67.89
[A] www.mydomain.com 123.45.67.89
or option B:
[A] mydomain.com 123.45.67.89
[CNAME] ...
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4answers
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DNS NS Records vs A Record
I wish to have someone point and resolve their domain to my web server to begin serving their pages.
Is it enough to have the person set only the NS1 and NS2 records to my name server, or must they ...
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1answer
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Wildcard 'A' record overriding CNAME record
I have a Wildcard * A record for self-registration of subdomains by users on our web app. All works fine.
I now need to set up an alias for support.mydomain.com to point to mydomain.freshdesk.com. ...
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4answers
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Is setting an empty/blank DNS A record allowed?
I'm trying to wrap my head around the wonderful world on DNS.
I have created a zone file for example.com which contains:
@ A 1.2.3.4
* A 1.2.3.4
However I am also setting up my local ...
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3answers
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CNAME versus an additional A&AAAA record
So, let us say that we have set-up an A record and an AAAA record for @, and for www we have set-up a CNAME pointing to @.
When a new visitor visits example.com and the webserver sends a 301 ...
3
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2answers
170 views
Is @ the same as the IP address for @ in the MX record entry of a zone file?
I have the following configuration in my DNS Zone. I want to switch the @ record to a different IP address, but I want to keep the MX records the same. Please note the IP address has been changed to ...
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1answer
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Multiple DNS records pointing to a single domain
Our business currently subscribes to a DSL internet connection. We're moving away from this and in fact will have two 3Mbps dedicated fiber connections run into our operations center in the coming ...
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5answers
302 views
Is Downtime Needed after changing the Ip Address of A Subdomain?
I have a subdomain whose DNS A Record I would like to change. After doing this, do I have to wait for some time before the change will be reflected?
If yes, during the downtime is it possible to put ...
2
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3answers
249 views
A-Record Failover?
I have a Fortigate 100D with 2x BT Business Infinity Fibre connections acting as WAN1 & WAN2.
The BT lines come with 5 static public IPs each and I have my DNS hosted through CloudFlare pointing ...
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3answers
320 views
Do CNAME records overrule A records?
I have several A records like so:
Subdomain IP Address
example.foo.com 1.2.3.4
foo.com 1.1.1.1
And a CNAME record that looks like this:
Alias Destination
www.foo.com ...
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4answers
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Redirect subdomain.example.org to somethingelse.com hidden to the user?
I'm not knowledgeable at all about C-NAMES, A-RECORDS, name servers and the like, so just bear with me on this one:
I want to redirect subdomain.example.org to another domain somethingelse.com. I do ...
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3answers
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Website doesn't work when missing “www”
Does anyone know the solution to this problem?
I checked my zone file and there are 2 A records
mydomainname.com. 14400 IN A ip.address.x.x
localhost 14400 IN A ...
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2answers
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CNAME, A, and Apache - Why does one work and not the other?
I have a website, example.tld. The DNS has an A record for example.tld that points to 1.2.3.4.
Is there any difference (as far as Apache is concerned/configured) whether a sub-domain ...
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1answer
2k views
How to set up a BIND DNS server to respond a single IP address to any request on Windows?
I want to configure a BIND DNS server (since Windows Web Server 2008 does not have DNS service, I had to install BIND) that responds any request with a single A record. I had set up a * record but it ...
2
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1answer
187 views
Registrar and Host are Different - Should I move DNS?
Registrar and Host are different companies. Obviously A, MX, CNAME, TXT, SRV should be changed. However, should I move Domain Name Servers to the Host or keep them with the Registrar?
Thanks.
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Is there a way to force A-record removal in DNS from client server?
Is it possible to initiate deleting of DNS A and PTR records in DNS from member server?
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CloudFlare offers DNS root CNAMEs. Any resolution gotchas to be aware of?
I'm not that familiar with the inner workings of DNS, preferring to just add my CNAMEs and A records as appropriate, and leave the behind the scenes to other services. I host a few sites on Amazon S3, ...
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1answer
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Is it possible to simplify my website DNS records?
Let's say I have mydomain.com and my shared webhost server is 1.2.3.4. My domain registrar and webhosting company are 2 different entities.
Currently I have my DNS records configured like this in my ...
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1answer
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MX and A Records
Just a quick question about A and MX records.
If I have a domain that I have purchased, and I want to get remote mail working eventually, to say: mail.exampledomain.com, do I just put in with my ...
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2answers
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Is it possible to add wildcard serveralias to virtualhost without modifying httpd.conf manually?
Is it possible to add wildcard serveralias (example: *.somesite.com) in an apache server without modifying httpd.conf manually? I use a DNS different from my hosting server and i have added asterisk A ...
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2answers
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nginx www.domain.com vs domain.com virtualhost
I have an http block where I include virtual hosts for the different domains hosted on the same server. For each virtual host I do:
listen domain.com:80;
Now, domain2.com works fine. However, when ...
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1answer
45 views
Is there any way to point an A record of a web page to another website when that other website is on shared hosting?
I am creating a web application that at this point I am using shared hosting to host. Is there any way for me to give my users the option to point the a record of their domain to my website and I ...
2
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1answer
199 views
Subdomain and CNAME
I have a website foo.com and now I have setup a sub-domain sub.foo.com. I can open foo.com and its fine but when I try to open or ping sub.foo.com its not happening. I cant even FTP into sub.foo.com. ...
2
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1answer
101 views
splitting A and MX records
I have a domain name which currently points to a shared hosting service. I've set up a dedicated Apache server for the web hosting, but would like to keep using the mail server of the old host.
Is ...
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2answers
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A and PTR records and redundant Internet connections
Want to set up PTR record(s) to handle the following:
Site with mail server (Exchange 2010) has three Internet connections, with the firewall handling load balancing.
I know that if the Internet ...
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3answers
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what is an A record and how it is related to DNS?
i dont know what A records do.
and are they necessary for a web server to host multiple domains and how are they related to DNS?
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Sending an Email from 2 Mail Servers
We are currently attempting to move away from using a "local" mail(exchange) server to an cloud based offering for all our automated emails. The problem is that we send and receive thousands for ...
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2answers
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Using www.example.com as the A record
I want example.com and *.example.com to always resolve to www.example.com
So if I set the DNS records as:
www A server ip
(root) CNAME www.example.com
* CNAME ...
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1answer
164 views
DNS not resolving for root domain, only for subdomains
The domain I'm having issues with is rossmasters.com. Here's what happens when I attempt to resolve the root domain and a subdomain:
C:\Users\Ross>nslookup rossmasters.com
Server: UnKnown
...
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4answers
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Preventing MX record fallback
I have a website, example.com, running on a Windows 2008 server with IIS 7 and the "IIS 6" SMTP service. The website regularly sends out emails to info@example.com.
In rare instances, the MX record ...
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3answers
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Domain resolving problem
I have registered a new domain. I want to use it with my server. I have a static IP for my server. Using my registrar control panel I have added an A record for my domain.com with value IP of my ...
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2answers
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Multiple DNS A records referencing the same host
If I create multiple DNS A records for the same hosts, for example:
my-domain.com A 1.2.3.4 3600s
my-domain.com A 4.5.6.7 3600s
my-domain.com A 7.8.9.0 3600s
Do queries really ...
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2answers
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Change DNS A records dynamically
For example, I'll buy domain name at godaddy.com. I'll configure it with 2 A records with IPs 123.0.0.1 and 123.0.0.2.
Is it possible to ping it for availability and change A records dynamically by ...
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4answers
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DNS not resolving for *some* people/locations
We created a new sub-domain (via A record) but it is not resolving for everyone. It's been working for me and some others for about a week, but others still cannot access the site. I don't think ...
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3answers
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Getting a list of DNS records for multiple domains [closed]
We have over 250 domain names with one registrar which, due to years of organisational neglect, point to various different servers hosting the websites.
I've been asked to clean this up. sigh
To ...
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1answer
143 views
Bootstrapping A Records for a DNS Server
My problem is this.
Dissatisfied with the existing free DNS nameserver solutions, I decided to make my own nameservers for my websites. I'm using NSD on Debian, and it's working great. I can request ...
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1answer
87 views
Possible A Record Conflict
I just inherited management of the domain names from another person who resigned from my company. I am new to this type of task.
I want to map the new ip address I bought to the following example ...
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1answer
123 views
Subdomain A record, how to proxy subdomain MX record
I have a subdomain of a site, lets say foo.example.com which has an A record to the IP of another server, lets say example2.com. Ideally, I would like to have the example2's server also take care of ...
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2answers
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How to set up CNAME to point to Azure
Here's the story. I have an application on azure. I would like to set up an A-record. My main domain is myhost.dk and my azure adress is myhost.azurewebsites.net. The Azure guide says that I have to ...
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205 views
Redirect domain to Dreamhost by changing A Record only
I bought a domain somewhere else and tried changing the A records there to the DNS nameservers that Dreamhost uses (66.33.206.206), but it didn't work. Is there any way to have my domain redirect to ...
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2answers
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PowerDNS CNAME with multiple A records produces unexpected results
This problem from what i can tell is isolated to PowerDNS. The servers are running two packages pdns-static-3.0.1-1.i386.rpm and pdns-recursor-3.3-1.i386.rpm on the most recent version of Amazon ...
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1answer
208 views
issues getting apache to serve phpmyadmin from subdomain
After years of using managed servers I'm finally getting my feet wet with setting up a webserver (using rackspace cloud). Here is how I have things setup:
Server A (hosted with servint.com, manages ...
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2answers
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What happens when I change a Name Server record or an A record in the Zone file or the DNS settings?
I don't really understand how the internet and DNS works. I am inundated with terms I don't understand when trying to read about it on wikipedia. I don't have a computer science background.
When ...
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3answers
110 views
DNS issue with migration of web site to new server
I have a legacy system that I'm attempting to make a significant configuration change to, but am not seeing a way to do so cleanly.
The state I inherited consists of a web site hosted on two app ...
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1answer
87 views
Subdomain mapping to domain
What happens if you have 2 DNS entries:
Name | Type | Value
-------------+-------+--------------
example.com | A | 20.20.20.20
example.com | MX | mail.example.com
Does this ...
