The Domain Name System (DNS) is a hierarchical, globally distributed system responsible for associating the name of a computer, service or other resource into an IP address for connecting to the Internet or a private network. Most prominently, it translates domain names to the numerical IP addresses needed for the purpose of computer services and devices worldwide.

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I guess I have to read up on DNS more.  I thought I understood the basics... but maybe not.

Setting up hosting for email and DNS on a new web hosting company (keeping the website where it is for now).

The guy that build the website and has the web and DNS name servers at wix, sent me these entries (besides others for MX, etc), but I am confused.

ourdomain.com      A
ourdomain.com      A
webmail                  A
mail                  A
www                  CNAME      www243.wixdns.net.
m                  CNAME      www243.wixdns.net.

That www243.wixdns.net resolves to  

if you type www.ourdomain.com you go to www243 which resolves to ...186?

But if you type ourdomain.com in a browser, it goes to ...147 or ...100 (in round robin?)

(typing ourdomain.com in a browser, it changes to www.ourdomain.com and the website loads.

and what's the difference between making WWW a CNAME vs. A record?
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I had this question after viewing DNS not resolving for specific website.

I have a same Issue like. Our DNS server not responding to the certain address
Hi, I am trying to join my computer to our domain but I unable to do so due to issues with discovering the name server. when i run nslookup it returns with a server unknown with an IP V6 address. I have a slight inclination as to the issue is but could not know how to troubleshoot it. On the DNS server someone as crated both multiple host records with different names pointing to the same IP address in both IPV4 and IPV6. However the IPV4 records in  SBS Server 2011 can have reverse lookup records where as IPV6 do not. I know IPV6 should have the capability to do a reverse lookup. Please help.
Setup of DNS - 1 in my DMZ and I in ISP location - public DNS servers

I'm receiving feedback from some external experienced engineers that the above setup is weird. I sense there my be something wrong - but from what ive researched this is good practice.
They are both primary authoritative name servers for our public domain. - there is no zone transfer between them.

The ISP controlled DNS is frustrating to a degree as we need to ring them frequently to get unusual entries completed. EG SPF records. Then I need to place the same record in my DMZ on-prem hosted DNS server (which i can do myself easily). So there is double entry required.
The question I'm asking is is this an unusual setup for public DNS for an organization?. Whats wrong with it ? Thanks
Single exchange server.
5 e-mail domains
Two mx records
One spf record in one „primary“ domain public dns.
Spf v=spf1 mx –all

What about other 4 domains

I think that someone trying to spoof this 4 domains e-mail addresses and sends spam.
Do I need to add spf record to other 4 domains and how to configure spf for other 4 domains.
I have a hyper V lab environment setup. I originally had it setup to a internal switch but wanted to change it to a external switch so I can get out to the internet.
 I can get out to the internet if I set that machines to automatically get a ip address but I need to be able to communicate between the machine in the lab.

At my work place they have it setup so all the machines use the DC for DNS resolution and they set forwarders on the DNS server to get out to the internet. This doesnt seem to work in my lab envir. Is there a way to get the machines to see each other and get out to the internet as well?
A long time ago I set up web / dns hosting for my domain and a bunch of clients.  somewhere I saw the idea of rather than ns1.networksolutionsy.com (just an example, don't think that's the correct URL) , that you could set up ns1.yourdomain.com  for the name servers  - i think it's just a cname in my DNS zone?  Actually looking now, it's an A record resolving to the IP of the web hosts' name server IPs.

But I remember there were some caveats / things to be aware of.  I'm looking to change things and the name server will change.

Anyone know what the caveats are?  Say I want to use godaddy's name servers for the different domains I control instead of networksolutions.  Can i just get the IP addresses of the godaddy name servers and change the A records for ns1 and ns2 in my domain zone and then at least the other domains.  but for my domain iteself?  There was something about trying to resolve ns1.mydomain.com but it has to look up my name servers first.... and that's a vicious cycle?

Anyone know what I'm thinking of / what the resolution was? because it is workingl and has been for years
I am in the process of moving my KMS server that will be hosting two domains.
I have made the DNS change for both domain DNS to point to the new KMS server.

_VLMCS._tcp.OldDomain.local        SRV service location:
          priority       = 0
          weight         = 0
          port           = 1688
          svr hostname   = vollic.NewDomain.local
vollic.NewDomain.local       internet address =

I can ping it from any machine on either domain.
When is set the SKMS to force it to talk to the new KMS server it does register successfully.

The issue I am having is if you allow the client to auto discover it registers with the oldDomain KMS server.

DO I just have to wait it out?
The above location is a Microsoft Network Load Balancing Cluster and has a Cluster IP address of and DNS of test.com (IP and hostname not the real ones)
The cluster contains 2 servers test1 ( and test2 (

When you ping the DNS name we receive ping responses from other IP addresses (e.g. and 78 etc).
What is the reason behind this?
We have multi site AD . Each site has internal DNS . How do i make sure that DNS get updated immediately when we make change instead of waiting for AD to replicate it.
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New Exchange 2013 installation. Want to confirm that my internal DNS server has the correct Autodiscover, mail, webmail entries. I have just entered the entries on my SANS cert into our internal DNS server but I have doubts whether this is working correctly 100%. This DNS server and email server sit in our .local domain.
I need some help in understanding what is the "DNS"? What is it exactly? Do I need to have it? If so which one do you recommend?

Thank you,

Basem Khawaja
I am having replication issues with one of my DC's (Windows 2012 R2), that also serves as DHCP. Sites & Services, it is set to auto replicate but it doesn't and force replication errors out with RPC not running even though it says it is in services. It will ping all servers except the gateway (all other servers can ping the gateway. I have checked DNS and can't find any 'obvious' issues. Is there somewhere else that I should be looking?
Hello Experts - I have a question about making an MX record change.  We are using Barracuda's email filtering service and they are asking that our MX records be pointed to the following addresses:

Primary: d35456a.ess.barracudanetworks.com
Backup: d35456b.ess.barracudanetworks.com

Currently both MX1 and MX2 point to individual Barracuda IP addresses.  The records are hosted with Network Solutions.  When I sign in, I navigate to the Advanced DNS section to edit but the form requires a numerical IP address and won't allow me to enter the addresses above.  I feel like I'm missing something here, any ideas?
Hi Guys,

Got an issue in a small network.
all the websites working, except anz banking site login.
the anz website works, i can browse through the site. its just the anz internet banking login page. when users enter their credentials,
it keeps loading and comes as page not available. after spending some time, i found out its dns issues. but could not fix it properly.

if i do ipconfig/flushdns - its working good. again if i restart computer. it does not work.
so my temporary fix is - after restarting/turnon computer i need to run ipconfig/flushdns to make anz site works.  
and it happens in all computers.

and i tried changing dns settings in router and also giving static ip in computers. nothing works. only flushdns command make it work.  
how do i fix it ? any solution.

thank you guys
After exchange 2010 to 2013 upgrade none of my Outlook clients can connect to the new exchange server. AutoSync and OWA connections are OK.

When creating a new client profile I receive the message "The name can' be resolved". NSlookup is good. Inspection of DNS server shows A record good for new exchange server.
we have configured a new Server 2016 DC and and new Exchange 2016 sever (on separate hardware).

We are not able to get our iPhone's to setup an Exchange account. The account on the phone will all 'green tick' but when trying to collect email is comes up 'account error' - 'unable to connect'.

This is a summary of what DOES work.
DC is working fine
Exchange is working fine
We have configured various DNS settings on our DC to reflect out external URL, Autodiscover, OWA and remote - they point to Exchange
We have a WIldcard SSL that gives us a secure SSL connection from outside our organisation to the DC's RWW and Exchange OWA
Internally Outlook clients can connect fine
Externally - NON DOMAIN joined PC's can configure a Exchange account and CAN send and receive email.
We have configured AUTODISCOVERY (URL 'A' and 'Cname' records) - and according to Microsoft's Remote Connectivity Analyser all tests pass - EXCEPT IMAP and POP which is due to the Wildcard SSL NOT being bound to those two protocols (but shouldn't be an issue- i don't think)

I have tried setting up the Exchange account on iPhone 6, 7, X iPad 2 and iPad Pro - none work and all show the same connectivity issue with Exchange.

We seem to have setup everything correctly - but clearly there is something missing.

Can anyone offer any support please
Thank you
Very rusty with this. Working on an SBS 2010 standard.  Mail is not going out.  It's the weekend.  I see 58 emails in the send connector queue.

The connector was set up years ago to use a web / email hosting company as smarthost.   it's talking about authentication errors.  If the hosting company stopped that account  set up in the send connector, what other options do we have?

What companies are out there to let us use as a smart host? Why do we need a smart host? Why not be able to just push the emails out onto the web?  And how would we set that uo?


talks of choosing use dns and MX to route mail.  Can we just use that? What's the pros / cons of doing that?  And /or how do you set up a 2nd smart host entry - if it can't send mail with first, smarthost, failover to 2nd?
Windows DNS issue.  Customer added on-premise Exchange server.  Since doing so, their is a problem accessing their public website from within the network.  The website is designed to strip the www prefix. When accessing the website www.domain.com it strips it to domain.com.  The AD domain is also domain.com so when the website tries to redirect to domain.com it goes to the internal DNS which is the Exchange server.  Need assistance in configuring DNS so it continues to route to the public website when the www is stripped and not effecting any Exchange 2016 functionality.
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We currently have 2 DCs onsite and 1 DC in Azure. There are more times than not, our building has a planned power outage and we have to shut down our servers. However, our Cisco ASA is still up and we want the DC in Azure to pick up DHCP/DNS. I'm not sure how to go about this or where to look.
to vote  


I have a client who outlook 2013 emails just sit in the outbox

Recreated the profile
Unjoin from domain
Join the domain
Flushed DNS
Used static IP
Turnoff off cached mode
Update the network driver
Running wire shark now

Send Immediately” is enabled in Advanced settings.
 Windows Firewall - Turn off and try
Kicked it hard

I have enabling logging in Outlook 2013  the %temp%\outlook logging\OPMLog.log file logs no events of receiving items at all. There have been messages received, and yet no trace of them in the OPMLog.log file. This is the case for an Outlook 2013 client  using the same Exchange server 2013

OS is Windows 7 x64 (Office 2013)

It does not seem to matter if I tag or untag Online Mode or Cached Mode. As well as it does not matter if I tag or untag the "Oultook Anywhere" or RPC over HTTP.

 Synch operation completed
 2018.09.14 12:46:12 Sending done, Error code = 0x00000000
 2018.09.14 12:46:12 Sending done, Error code = 0x8004010f
 2018.09.14 12:46:12 MAPI Status: (IN -- ---/OUT -- ---)
 2018.09.14 12:46:12 Finishing the Spooling Cycle, Error code = 0x00000000
 2018.09.14 12:55:12 email address : Synch operation started (flags = 00000001)
 2018.09.14 12:55:12 email address : UploadItems: 1 messages to send
 2018.09.14 12:55:12 EXECUTING Put MAPI TASK
 2018.09.14 12:55:13 Starting the Spooling Cycle
 2018.09.14 12:55:13 MAPI Status: (IN -- ---/OUT fl ---)
 2018.09.14 12:55:13 MAPI XP Call: …
H we have i sharepoint appp - and a need to retire a DNS server. We have an entry in DNS we cant point to a new DC DNS server and we want to retire old dns server

Ok After digging a bit deeper into sharepoint we have found that its a custom app - please read:


Now the issue is in our zone apps.intranet.domain.com.au there is no wildcard CNAME entry - there are no entries at all other that the pointer to the name server.

so is it a matter of just deleting the zone - recreating on the new DNS Domain controller - and creating a CNAME wildcard - not sure how these sharepoint apps work - can a SharePoint person help?  thanks
We have 2 domains within our forest, Domain 1 and Domain2.  Both domains are part of a secure private network. Some of the hosts in Domain2 are public facing and and have both public/private IP addresses. eg host1.domain2.com has private address and public address Domain1 has a conditional forwarder to an internal DNS server within domain2; dns.domain2.com.
If there is a network problem between the 2 domains or dns.domain2.com is rebooted, clients in Domain1 are resolving address for host1.domain2.com. This address is not valid on the private network (I can exlain this further if need be), clients can't connect to it and they also cache it for serveral hours.

Is there a way to prevent DNS requests for domain2.com being routed to the internet if dns.domain2.com is unavailable?

I am managing two separate locations, both have a single 2008 R2 DNS/DHCP server and they both hold the FSMO roles. I want to create a secondary DNS/DHCP server at each location for redundancy. Here is where my problem lies, I have 2 servers running server 2012 R2 to use as the secondary. I have had no issues setting up redundant DNS with the 2008 and 2012 boxes. I've hit a roadblock with DHCP and i'm not liking what Google has to say.

Ideally i'd like to run a DHCP hot standby with the 2012 box. Load balance is an option as well if needed. One site would have no issues running a split scope as i only have ~60 devices. The other location has almost 200 devices, a split scope would be difficult to pull off.

I cannot upgrade the 2008 r2 boxes but i can downgrade the 2012 r2 boxes to 2008 r2.

Any thoughts or ideas would be appreciated.


What are some reasons for not being able to ID my DNS server (specifically on my android phone)? My isp is At&t.  It's not that I don't have an address to lookup. It's more so that the windows nslookup command and the website https://www.whatsmydns.net/ yield no results.
Also, if someone could provide some mitigation steps or useful references  .

Much appreciated






The Domain Name System (DNS) is a hierarchical, globally distributed system responsible for associating the name of a computer, service or other resource into an IP address for connecting to the Internet or a private network. Most prominently, it translates domain names to the numerical IP addresses needed for the purpose of computer services and devices worldwide.