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 have two 3750 switches that are connected and working but here is my only issues. By the way I am very new to networking so please excuse me being naïve .

My issue is when I have a machine on a different subnet other than the main one 10.46.72.x DNS does not resolve even though I manually add and with a DHCP scope that I removed will not work. Can someone please tell me what  am doing wrong. Here is a copy of the config


User Access Verification

Base-sw1>show running
Base-sw1#sh ru
Base-sw1#sh running-config
Building configuration...

Current configuration : 3753 bytes
version 12.2
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
hostname Base-sw1
enable secret 5 $1$lwLf$CJoNDGBl4Ck6AAm/woBVM0
enable password secret cisco
no aaa new-model
switch 6 provision ws-c3750g-24ts
system mtu routing 1500
ip subnet-zero
ip routing
no file verify auto
spanning-tree mode pvst
spanning-tree extend system-id
vlan internal allocation policy ascending
interface GigabitEthernet6/0/1
 switchport trunk encapsulation dot1q
 switchport mode trunk
interface GigabitEthernet6/0/2
 switchport trunk encapsulation dot1q
 switchport mode trunk
interface GigabitEthernet6/0/3
 switchport trunk encapsulation dot1q
 switchport mode trunk
interface GigabitEthernet6/0/4
 switchport trunk encapsulation dot1q…
Microsoft Azure 2017
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Microsoft Azure 2017

Azure has a changed a lot since it was originally introduce by adding new services and features. Do you know everything you need to about Azure? This course will teach you about the Azure App Service, monitoring and application insights, DevOps, and Team Services.


I understand that there is  HealthMailbox in Exchange 2013.

Based on the message logs, there are a lot of email coming from contoso.com. I don't know why domain shows as consoso.com.

Would there be any issue if we delete HealthMailbox ?
What would be the impact on mailbox of the user if we delete?

How do I Move Godaddy account domain to another Godaddy account

[ Move Godaddy account domain to another Godaddy account ]

Issue is with finding "Domain Settings page"

1. Click a domain name on the list to go to it's Domain Settings page. [ Where is this Page? ]

2. On the Domains Settings page, below Additional Settings, click Transfer domain to another GoDaddy account.

3. The Begin Account Change window will appear

I am not sure if I interpret this correctly but this security report seems to show a few workstations have some suspicious DNS activities and trying to resolve some DGA domain - please see the attached.  

I am not in the security area.  Someone who knows how to handle please advise.  

Many thanks.
Dear Experts.

Need help on firewall ports requirment.

I have two different forest tbd.nal.nl and nsk.pwd.uk entity within same organization (no child domain).
Request experts help to suggest what are the ports minimally required for forest trust to work.

1. List of ports to be open in firewalls for forest trust.
2. Ports to open between forest domain controllers tbd.nal.nl and nsk.pwd.uk.
3. Do we require to ports to open tbd.nal.nl clients to forest nsk.pwd.uk domain controllers and viseversa, if yes can help us list of ports to open.
I do not have an issue but was wondering if you guys can list out some projects, problems or tricks you have done with Window DNS. I am trying to become more stronger in this area. I have a few but was trying to add to this.

Round robin DNS---Good for load balancing
Alias -- have used for a very long server name to shorten this for ease of use.
We're creating a DR location and i have a question about email. We currently use O365 along with a hybrid on-prem Exch 2013 mail server where we create onprem users/mbxs and then migrate to O365 cloud. We use onprem ADFS to auth. This setup is current and will not change at current production site. (wasn't involved in design but it will remain)

In the event of DR scenario, i will redirect external STS DNS A record to now point to DR location (as well as create an internal STS for DR site) to work with DR onprem ADFS server (we will use DR location ADFS, not Azure in cloud) to authenticate users. This part i believe is correct.

My question is the external and internal autodiscovery DNS A record. I know this is used for initial user Outlook setup, but i don't plan to be ready to make new users in the event of DR scenario. Only planning for short duration at DR location before moving back. (perhaps optimistic :) but this is the plan)

I will not have a hybrid server at the DR location. So - I don't need the autodiscovery DNS A external and internal record as it will have nothing to point to, and is not then needed for this temporary time, correct?  Am i wrong?  and if so - what's the autodiscovery purpose at a temp DR location and what would it point to without a hybrid server at DR?

Any link to confirming information would also be appreciated. Thanks guys/girls!

As part of a local football club, I email out newsletters through Campaigner from our club's email address to subscribers of newsletter which details news for the club.

There are 250 people who receive the newsletters and they had subscribed to the newsletters themselves.

Until recently, these newsletters were delivered successfully each week.

For the last few weeks, these newsletters have been sending to the subscribers' spam folders.

To fix this problem, we set up or DKIM and SPF records correctly for Campaigner.

This week 4 out of 250 people received the newsletters correctly.

Mostly all of the subscribers use Gmail.

If all subscribers put in the club's email address, where newsletters are sent from, into their contacts in Gmail would that solve anything?

What are your thoughts on this matter?

I had this question after viewing DNS Amplification DDoS Attacks.

IN this case i work for an ISP company....What do you advice as a possible fix
I need to add a spf record to avoid spoofing and I use register.com as dns provider. They told me to add the following into the txt record.

@     "v=spf1 include:spf.registeredsite.com ~all"

I did that. When I sent a test mail to my gmail account, the mail went through but the header showed me it is has a softfail and the error message is as following:

pf=softfail (google.com: domain of transitioning me@mysite.com does not designate as permitted sender) smtp.mailfrom= me@mysite.com;

For your information, my A record is the following:

*.mysite.com     <- webserver
mail.mysite.com   <- emailserver

Note: Please pardon the email address and ip addresses in this post are not real for security reason.
C++ 11 Fundamentals
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C++ 11 Fundamentals

This course will introduce you to C++ 11 and teach you about syntax fundamentals.

So we were using a Local Exchange server with the domain of 123abc.com. Our local AD domain name is 123abc.local. We have decided to move all the email accounts to Office 365 under a new domain name of 456abc.com. That portion of the project went good, set up the office 365 mail server migrated the email over to office 365, added the original domain of 123abc.com to the new office 365 account as an allis domain and added all the old emails test@123abc.com as an alias email to the Office 365 email. I have also gone thru and set up the outlook clients to use the new domain and everything is working fine. The issue is now that everything is on office 365 I shut down the local exchange server and now some of my users are getting a mail cert error. Certificate Error
I have found that if I go in and follow these instructions and add the exclude SCP object check, outlook no longer throws up the error. The issue I have is I have over 50 machines and I know I can export the reg and import into other computers, but there has to be an underlying issue and a way to fix it without having to import reg on every machine.


Also, anything anyone can recommend that I can read about decommissioning a 2010 exchange server on a local domain? I think I would need to remove it from the domain but what else should I remove?
I'm having issues with certain addresses resolving to an internal IP address when I don't think they they should.

We are running Windows 2016 Active Directory/DNS and have our domain zone record hosted with the same company who host our website.

Our AD domain is ad.company.com and the website is www.company.com. This works fine and requests from both internal and external all resolve to our host and we can see the website.

We host an internal ftp/web server with A records set up at the external company for ftp.company.com and company-webservices.com, both of these are set to point to the external IP of the web/ftp server. External requests to either of these work correctly and customers can see the ftp and web server.

What doesn't work is requests from the LAN. These resolve to the internal IP of the ftp/webserver.

I could possibly understand this for ftp.company.com but not for company-webservices.com as that is completely unrelated to our AD domain.

How do I go about fixing this so that LAN requests to ftp.company.com and company-webservices.com resolve to the external IP of the server?

How do I recover ownership of expired whois.godaddy.com domain name

Domain Name schoolforthearts.org is owned by me (Jim Lacey of  as  JAMAR Associates)  as of 11/27/2016 as listed in ICANN WHOIS.

Registry Domain ID: D103541157-LROR
Registrar WHOIS Server: whois.godaddy.com
Registrar URL: http://www.godaddy.com 
Updated Date: 2010-11-17T19:08:48Z
Creation Date: 2003-12-23T23:51:04Z
Registrar Registration Expiration Date: 2018-12-23T23:51:04Z

This domain was listed by GoDaddy as Parked for Free - but now seems to be for sale, apparently because of earlier expiration date.

Current user of this domain needs resolution as customers cannot access website, domain listed as 'parked for free, courtesy of GoDaddy'.
I have a vm running 2008 server (not R2) that is a primary domain controller and DNS server.   I have 2 vm's now running server 2016 (server2016-dc1 and server2016-dc2). I would like to make DC1 the primary domain controller the demote the 2008 server to a member server.  After that is done DC2 (2016 server) will become backup DC and DNS.  

Is there a good document that will help me step through this?  Also, do I have run adprep on the 2008 server first?  I read something somewhere that indicated that 2016 does this for you.
Upgrading from Exchange 2010 to Exchange 2016. Everything is connected and communicating. However, whenever we point the external interface to the Exchange 2016 server, Outlook anywhere for any mailbox on the 2010 server fails to connect. OWA and Activesync works just fine. Internal connectivity is fine. Just Outlook Anywhere. I have gone through the co-exist configuration, setting Outlook Anywhere to an external mail.crestoperations.com, which is my external DNS to our NAT firewall (the only thing I change is the NAT pointer). I have configured Outlook Anywhere on the 2016 server to use NTLM. I have configured IIS on the 2010 server to use both basic and NTLM. Any advise on configuration would be appreciated.
We have 2 Server 2012 r2 domain controllers running in VMWare. File replication has been failing with the following event viewer error on DC2 :

Log Name:      File Replication Service
Source:        NtFrs
Date:          1/3/2019 10:14:44 AM
Event ID:      13555
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      MB-DC2.ad.xxx.com
The File Replication Service is in an error state. Files will not replicate to or from one or all of the replica sets on this computer until the following recovery steps are performed:
 Recovery Steps:
 [1] The error state may clear itself if you stop and restart the FRS service. This can be done by performing the following in a command window:
    net stop ntfrs
    net start ntfrs
If this fails to clear up the problem then proceed as follows.
 [2] For Active Directory Domain Services Domain Controllers that DO NOT host any DFS alternates or other replica sets with replication enabled:
If there is at least one other Domain Controller in this domain then restore the "system state" of this DC from backup (using ntbackup or other backup-restore utility) and make it non-authoritative.
If there are NO other Domain Controllers in this domain then restore the "system state" of this DC from backup (using ntbackup or other backup-restore utility) and choose the Advanced option which marks the sysvols as primary.
If there are other Domain …
I  am now working for a company that has 2 external dns servers and no one knows what maybe using them if anything anymore.
Just wondering what is the best way or easiest way for me to find out what is using these 2 external dns servers?
Thanks in advanced.
URL Masking

I am reselling an online product and using my own brand name (all contracts with product provider in place).

They have an Outlook Web Access url which lets say is https://supplier.co.uk/owa. Now, I want to have my own domain for the same but so that my clients don't ever know they are using the suppliers URL. So something like https://owa.rebrandedname.co.uk or https://www.rebrandedname.co.uk/owa

How can i achieve that without redirect all traffic for all pages to www.rebrandedname.co.uk
We have a user that works at two locations. He is running Windows 10.
At location 1 he has DHCP with the DNS IP addresses he needs.
At location 2 we need to manually set static DNS for him to access some crucial applications.
We don't just leave the static DNS IPs on because this affects his normal internet access when at home or elsewhere.

I would would like to setup two command files (.CMD) that will change the DNS settings for his NIC per location.
 - Command file 1 - DHCP DNS
 - Command file 2 - Static DNS

What command line can I use to do this?

Exploring SQL Server 2016: Fundamentals
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Exploring SQL Server 2016: Fundamentals

Learn the fundamentals of Microsoft SQL Server, a relational database management system that stores and retrieves data when requested by other software applications.

Just cleaning out my DNS and I see this greyed out local subfolder. It has a NS record that shows an old DC that has not been in use for awhile. Is it safe to delete?
Please see picture.

Thank you.
Ok so im trying to understand how i can mask my domain name across different web hosts.

So my setup is as follows:

Godaddy hosts my domain name: example.com
Example.com name servers are set to digital ocean
example.com website is hosted on digital ocean
My app for example.com is hosted on azure at example.azurewebsites.net
I want to create some links from example.com to example.azurewebsites.net but mask the domain name so users dont think they are leaving example.com

Is this possible? I assume i need to do something with DNS records and then something on the webserver for example.azurewebsites.net ?
I applied windows updates to two servers this afternoon.  Tonight I am getting complaints about accessing domain resources.  

If I do a nslookup google.com   it responds with the correct address.   If I do a nslookup fs-server-01  i get   *** DS-Server-01.vs.mydom.com can't find fs-server-01: Non-Existent domain.    

I have added a domain suffix in dns settings and this was working earlier today.   I have restarted DNS on both DNS Servers.  (DS-Server-01 and 02).  Both servers are running Windows 2016 Standard

Has anyone had similar issues?
Joining remote server to the Domain.  What the DNS should be on the joining server?  Local or remote domain that I am trying to join?
When this client connects to our Public guest WiFi her browser doesn't load. it comes up blank and she's not able to connect. It used to work. I had to delete the the public wifi during a large conference and then re-created after the conference. Ever since i recreated it she's not able to connect. I've not had another problems with any other devices. Her Kindle Fire version is 6.3.4_user_4120720. I don't have access to her device but if you could give me a couple ideas that would be great.

Is there a way to "Forget" the SSID or clear DNS on the Kindle Fire? any ideas would be most appreciated

I've opened a ticket with Ruckus support but that's not going to help me tomorrow (Sunday) when she'll try to connect again.
Hi Team,

Please help me to resolve this issue.

Please Check attached .jpg diagram of my infoblox environment.

1)      Earlier they had Microsoft server in all their location all individually working as primary and in sync with each other using Replica feature
2)      Now After infoblox when we make Microsoft role as secondary then only zone sync happens
3)      So traffic flows from Microsoft to infoblox, then from infoblox to DNS Proxy Forwarding and then to cloud
4)      We have told to install DNS Proxy Forwarding to get visibility of user based logs
5)      Also we have installed Reporting VM

1)      They are using infoblox just for DNS purpose only and not for DHCP
2)      They have individual DHCP servers on their different locations and their Microsoft DNS servers are acting as AD as well
3)      So whenever a new PC is added in domain or any PC changes its IP address a record is added in Microsoft but not on infoblox
4)      So for that we configured Updates on infoblox as suggested by TAC support
5)      Now the issue happening is that, when PC changes IP its earlier record is also present in infoblox and new records is also present, due to which when client connects to RDP he is redirected to another PC.

 For eg: - If A had ip- and after new lease allocated he has now ip as and is allocated to B, then there are four records present in infoblox
A- as static
A- as dynamic
B- as dynamic
B-earlier IP of B as static







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.