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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My laptops NIC is set to auto assign IP and DNS.  Should I change it to something else when I am connected to a mirrored port on a Cisco 2950?
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We think we're running into a limit on SPF record lookups. Does MX and A need to be in the entry? Do they count against it? Do only the IP addresses count against the 10 lookup limit?
What characters are counted toward the character count?
These aren't the ACTUAL IP addresses used but same count.
Is this record even look right?

v=spf1 mx a ip4: ip4: ip4: ip4: ip4: ip4: ip4: include:servers.mcsv.net include:spf.protection.outlook.com include:us._netblocks.mimecast.com -all
Event ID 4013: “The DNS server is waiting for Active Directory Domain Services (AD DS) to signal…"

This is our scenario:

We previously had an SBS2003 Domain a number of years ago
We setup a second Server 2012 DC and moved the roles to it
We shutdown the old SBS2003
The 2012 is a VM running on a 2012 Host
Recently we tried to move the VM to a new Host and it cause alot of DNS issues
We needed to seize all the FSMO roles on the 2012 DC and clean up the MetaData this weekend just gone
Now we are having major DNS problems and we are getting this error:
Event ID 4013: “The DNS server is waiting for Active Directory Domain Services (AD DS) to signal…"

It is like the DC is looking for the old SBS2003 Server and cant sync with it despite no trace of the old DC being left on the new 2012

Any assistance would be greatly appreciated.


This question is in regards to DNS tunneling. The abuse of DNS protocol to exfiltrate data.

Assume Windows client is able to reach his internal DNS server over DNS.  Only the DNS server is permitted to talk to the internet over DNS.  The client will be blocked from talking DNS out to the internet.

In my example above would the client be able to still be able to do DNS tunneling by relaying it through DNS server
We have an Exchange 2010 Hybrid w/ O365 setup for mailflow for @Ourdomain.com.
We use a cloud e-mail gateway that processes e-mail coming in and going out as well.
But we are looking to add a listserv server on-prem called "Sympa".  
We'd be looking at using listserv.ourdomain.com as a subdomain for the e-mail address for our SYmpa listserv.
Would we need to add a new MX record or just an A record?
We have ERP accessible thru website (https://.ourcompany.com) which is only accessed internally.  In DNS we have a HOST (A) record for(https://.ourcompany.com) to point to the public IP address of the server.

Setup OF DNS.


If we used the public IP address  (https://99.63.xx.xx.com) to access the website it works, it connects directly to our internal website.
Hello Experts,

I want to test DC site failure between 2 sites connected via a leased line. Both sites have 2 dcs each on Win server 2008. Both sites can communicate with each through our leased line.
Both sites have their own DNS and DHCP servers.  

The plan is to unplug both DC on one site and see if those on the other site take over and vice versa. This will simulate a complete DC site failure.

As I understand we will have to move our fsmo's role over to the active dcs when the others are taken down and also DHCP and DNS. If we did have a complete site DC failure on site1 I can I setup a DHCP and DNS in a disabled state in site2 ready to take over in case of an emergency.
from a whois on godaddy.com/whois
DNSSEC: unsigned

A website owner hires another person to blog his small business wordpress website
Website thinks his company is hosted elsewhere and thinks that his blogger has a dedicated server
I think it is hosted by godaddy
Maybe the godaddy nameservers point somewhere else

Is there another test I can show website owner where his website is hosted
I cant log into his godaddy or wordpress
We have three brand new Windows 10 Pro 1803 machines that won't connect to the local domain. We haven't changed anything recently as far as configuration. The DNS on the machines are set to the domain controller ip, we can ping the DC name, we don't have any software installed yet, firewalls are all turned off, and I have run a DCDiag on the server.
The results of the DCDiag were all "Passed".  I have tried entering the short name and the DNS name of the domain.

I did see an article that gave some command lines to use:
First command from work station on the domain djoin /provision /domain "YourDomainName" /machine "YourNewMachineName" /savefile YourNewMachineNameblob.txt
Run on new machine trying to join the domain djoin /requestODJ /loadfile YourNewMachineNameblob.txt /windowspath %systemroot% /localos

When we run the command it says the domain is not available or does not exist. Basically it can't see it. For all the basic tests that I know to do, the workstation can see the server, ping the server, see the shares, see the SysVol share but won't join.

Any thoughts?

We have a pc was rebuilt. WIFI works fine on that pc, but when we plug in a cable. The Internet is not working. We are getting this

"your computer appears to be correctly configured but the device or resource (dns) is not responding"

I have tried the following:
1. type in dns ip
2.ipconfig flushdns
3.ipconfig /registerdns   ---> "registration of dns records failed no dns servers configured for local system"

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Whats the best way to redirect a internal subdomain (test.company.com) to an external website (google.com). Using Windows DNS server. Thanks
I'm in the migration project for Exchange Online and using the MRS Proxy, but the internet link that is leaving the address of the endpoint is very slow.

Can I switch to DNS Externo for a fixed ip where it has a better link?
I have a Server 2016 Essentials Server. It works, it can see the internet, has DNS installed and all is fine. On this i have Hyper-V installed, and a Server 2016 Standard server. However, from the Essentials server (the host) i can not ping the VM. However, the VM can ping the host. Am i missing something
I wanted  to join Windows 7 PCs to the domain and I get this error.
An active directory Domain Controller (AD DC) for the domain Domain.Local could not be contacted. Ensure that the domain name is typed correctly. If I click the details I Note: This information is intended for a network administrator.  If you are not your network's administrator, notify the administrator that you received this information, which has been recorded in the file C:\Windows\debug\dcdiag.txt.see the below error:

DNS was successfully queried for the service location (SRV) resource record used to locate a domain controller for domain "Domain.Local":

The query was for the SRV record for _ldap._tcp.dc._msdcs.Domain.Local

The following domain controllers were identified by the query:

However no domain controllers could be contacted.

Common causes of this error include:

- Host (A) or (AAAA) records that map the names of the domain controllers to their IP addresses are missing or contain incorrect addresses.

- Domain controllers registered in DNS are not connected to the network or are not running.

Not sure if my colleagues had made any changes on the DNS. Please see the attached dcdiag.txt.
My PC is connected to the same network and subnet, I am able to ping all the three DCS.
When I ping from the workstations that needs connected to domain, I am not able to ping ADC-001 and ADC-002 , but able to ping …

I have Server in place for   as RTCServer1  with static IP Address and Alias record as WebServer1.  Now there is requirement from business to build new server with another static IP address but  Server must be named Webserver1. because of the   ERP  application restriction.  I think this will conflict with DNS record.

Please can any one  clear my confusion  is this possible to set new server with Similar name   of Existing Alias (CAME) Record.

Just recently, Gmail has been rejecting our company's emails based on reason of failed authentication.
We've never had a problem sending emails to gmail since 2004, but now, Gmail is saying that our emails are not following the
dkim, spf and dmarc guidelines. I'm not sure how to generate a dkim key and how to set it up on Netsol's DNS servers for
our domain (if I understand it correctly, after googling it). Any guidance is appreciated.  Thank you!
I created a new internal DNS zone to mimic an external domain:

old setup
internal zone - lawyer.local
external domain - lawyerfirm.com

new setup
internal zones - lawyer.local, lawyerfirm.com
external domain - lawyerfirm.com

The new internal zone for lawyerfirm.com contains two entries: mail.lawyerfirm.com and autodiscover.lawyerfirm.com.  I did this so that if I'm in the office, mail.lawyerfirm.com routes to the mail server's internal IP.  If I travel or am outside the office, then mail.lawyerfirm.com will route to the server's external IP.  So far, the setup seems to be working without issue.

Here's the problem I recently discovered.  The company website is hosted through GoDaddy (external).  When I'm outside the office, I'm able to view the website fine.  However, when I'm in the office, DNS fails to perform the lookup.  I did not add an A record to the internal zone for www.lawyerfirm.com, assuming that it would DNS forward the request.

Is there a way to configure DNS to forward the lookup to an external DNS server for any hostnames that do not exist in the internal lawyerfirm.com zone?  Or do I just need to create the A record in that zone?  I know the latter will resolve the issue, I just don't know if that is the correct method for future issues.

(please ignore any incorrect nomenclatures)
Dear Experts

in the Windows Active Directory domain controller environment joining the windows client to the domain controller by assigning the IP address and preferred DNS pointing to Windows AD server (which functions as domain controller and also name server).
 Joining the windows client does not require manually creating the entries in the forward and reverse zones, the moment windows client device is joined the records are automatically created in the DNS server.   Now how to make Linux servers in the network to use windows AD server as its  DNS server,  should we have to manually create forward zone and reverse zone entries and then configure Linux server to use windows AD server as its DNS server, please suggest .
I am Canadian based and have a bunch of email subscribers using a specific domain name (bissegger.ca, my family name).

For these users, email has to work. Hosting is secondary. When email is not working appropriately, I get the call. I'm tired of getting the call, I need a solution...

My main base of subscribers are only using iPad email. This ticket is to find an email provider that can use my domain name (so we don't have to change everyone's email address), that works well with iPad email, blocks most of SPAM - but if possible can host a .NET website.

1. I started out with DiscountASP.net - good .NET services but email settings had to be changed a bunch of times because the ISP would block the email ports, and I had users using several ISPs. Email issues came up a lot, and users received a ton of SPAM.

2. I moved to Namespro.ca, thinking that if I moved upstream to a DNS provider that things would get better - but they got worse. It never worked well with iPad default mail client, and had to install Outlook for iPad, retrain users etc... But was good at blocking SPAM.

The latest issue is that webmail works well (ie: no problem with Namespro), but email is being sent (with no error messages) but not being received by recipients. This means that there is something wrong with iPad or the iPad Outlook client. On all the users at the same time - obviously an iPad or Outlook update....

I am tired of this all, and would love any advice to know if there is a site…
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Dear Experts
Installed windows 2016 standard and configured it to function as domain controller, DNS server and DHCP.  It is observed the after promoting the server to AD domain controller the IP of the serer in the primary dns changed to local host I mean pointing to, manually changed to the actual IP.
While creating the forward and reverse zone had selected “do not update dynamic updates”
Following are the issues faced
1.      While joining the client system that is windows 10 pro to domain it accepted to join but message shown “preferred dns could not be changed” and then after reboot able to login with domain user. Please let me know where I am going wrong
2.      When the user logon and click on network browse the domain controller can see netlogon directory but does not show the user home directory, please let me know what I have missed.
3.      I made the normal user a member of domain administrator group in the server and then logon to the client system with this user but he does not get admin privileges when click on network to change IP address it prompts for logon and password but it does not allow administrator login to client system nor it does not consider this user as administrator who is actually member of domain admin group  
4.      Before joining the client system to the domain controller is required to create A and PTR records manually and then after join the system to domain
Please help me understand and suggest the steps to resolve the above 1 to 4, this…
We have be experiencing issues with the DNS servers that are being setup on DHCP clients. We have recently setup and configured Cisco Umbrella. The VA's have been setup and all DHCP scopes have been updated to use the VA's for DNS. All was working well or so it seemed but we started noticing DNS issues. ipconfig sometimes shows the correct DNS servers (the VA's) and sometimes shows the internal DNS server. The DNS servers change in between lease changes. Any advice on troubleshooting would be greatly appreciated.

I have computers on a separate subnet.  They are on windows 2012 Domain.  The DC is on a different subnet.  I have a Active Directory integrated zone on subnet 1 and the computers still cant contact the DC.  Example computers on the .1 network cant logon to the DC on .2.  A Active directory Integrated DNS zone is created on the DC in the .1 network.
Here is my set up:
2 domain controllers, Windows 2008 R2, 600-700 devices in the domain.  Everything is working well with no errors in the event log.

I am moving this customer to a hosted server outside of their LAN.  There is a site-to-site VPN established between the 2 locations.  The new DC is Windows 2016 Standard but the IP is in a different subnet.

When I try and add the new server to the domain I receive: An Active Directory Domain Controller (AD DC) for the domain xxxx.local could not be contacted.

In the details it shows the domain controller SVR records were found but they are not available.

I have verified DNS, I can ping from the new server to both DCs by IP and FQDN.  I added a static A record on the DC for the new server and I am able to ping the new server both by IP and FQDN from both DCs.  i have run DCDIAG and everything passes.  I can browse through Windows Explorer to the DC and see the shares SYSVOL and NETLOGON although I get access denied when I try and open them.

The only errors that I get are when I try and join the server to the domain or try dcpromo.
We have (2) 2008 R2 Domain controllers and we are getting ready to replace them with (2) 2016 servers. I have all the steps I believe to do the entire process but I do have a question regarding the IP address and name of the old 2008 R2 servers and the new 2016 Domain controllers.

There are a lot of items that use the dns from the 2 existing 2008 R2 domain controllers. So my question is, once we have the 2 new 2016 DCs in place and have demoted the 2 old 2008 R2 DCs, can I rename the 2 new 2016 DCs and change their IPs to the IPs and names that were on the 2 old 2008 R2 DCs?
Just trying to make sure that all goes smooth when we transition from the 2008R2 servers to the 2 new 2016 Dc servers.
I have added a server 2016 with essentials experience and ARR installed to an existing domain  with Exch 2013 already installed and a single gateway. All email is working fine, but I am unable to connect to the remote web workplace using the FQDN (remote.XXXXX.com.au/remote), internally I can access the RWA web site with https:// (IP ADDRESS)/remote but not https://remote.XXXXX.com.au/remote, the error is 404.

I'm assuming it is a DNS issue but I cannot see anything in the DNS, remote.XXXXX.com.au is pointing to the IP of the Server, I even changed autodiscover to point at the server, with no change to the behaviour. If I enter https://remote.XXXXX.com.au it resolver to https://remote.XXXXX.com.au/owa which may be a clue to what is going on.

The Essential experience server is not a DC but everything else works so I assumed that was not the issue.

Any assistance would be greatly 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.