DNS

Domain Name Services

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How To Use Nslookup To Check DMARC Record

Posted on by Rhoderick Milne [MSFT]
Check DMARC Using NSLookup

One of my customers wanted to verify their Domain Based Message Reporting Conformance (DMARC) record, and followed the post How To Use Nslookup To Check DNS TXT Record but ran into issues. They were not seeing any results.  Hmm strange; the DMARC record had been created and was visible in online diagnostic tools.  Why was it not showing up for them in a manual check?

The below is an example of what… Read the rest “How To Use Nslookup To Check DMARC Record”

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Intermittent Azure DNS Resolution Issues With With New Domain Controller

Posted on by Rhoderick Milne [MSFT]

The default option for DNS resolution on an Azure virtual network is to use the Azure DNS service.  This is perfectly fine for regular Internet requests, if you need the capability to register internal DNS records for Active Directory then you will typically need to run your own DNS service.  This is the case here and is also something observed with multiple customers.  In each of these cases the … Read the rest “Intermittent Azure DNS Resolution Issues With With New Domain Controller”

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How To Use Nslookup To Check DNS TXT Record

Posted on by Rhoderick Milne [MSFT]

Being able to retrieve DNS TXT records is very useful in multiple scenarios.  In this post we will look at checking the TXT domain verification record for Office 365 and also for the Sender protection Framework .

In addition to a MX record, we also have the option to prove domain ownership to Office 365 by using a TXT record.  Why do we want to manually check for these Office 365  TXT records?  Rat… Read the rest “How To Use Nslookup To Check DNS TXT Record”

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How To Check Exchange Autodiscover SRV Record Using Nslookup

Posted on by Rhoderick Milne [MSFT]

Generally the Exchange external Autodiscover DNS entity is configured as a regular A record.  Sometimes a service record (SRV) is used instead.  Since I have the habit of forgetting the syntax of quickly querying for the SRV record, this is one of those shared bookmark posts!

Nslookup is the tool of choice here!  Its documentation can be found on TechNet.

There are two ways to run nslookup – interac… Read the rest “How To Check Exchange Autodiscover SRV Record Using Nslookup”