Mailbag: Problem of the week: DNS Aging and Scavenging (getting the DNS record timestamp) with new Windows Server 2012 DNS cmdlets

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Greg here with a quick post where the new DNS PowerShell cmdlets in AD made a task much easier.

 

Many of our customers use Microsoft DNS and a feature of Microsoft DNS is the ability to remove stale records. By default this feature is disabled and some people never enable it, and others disable it believing it has deleted something it should not. Then years later they find they have 1000s of stale records and want to clean up this situation. The problem with our traditional cmd line tool DNSCMD is that it does not output the timestamp in a friendly readable format. There are other blog posts out there with scripts that sometimes work and sometimes we go onsite to help. Now we have a PowerShell cmdlet that will easily get this information for you. You do not need a Windows Server 2012 DC or DNS server you just need a Windows 8 or Windows Server 2012 machine with the new DNS cmdlets.

 

Get-DnsServerResourceRecord-ZoneName"demo.local"-RRType"A"|Export-Csvdemo.csv

That one liner will output all of the A records from a zone called demo.local and give us a file we can easily put in Excel to review these records.

This does not look pretty in a blog post so I have attached the file if you are interested in the output.

 

 

If you are not familiar with DNS aging and scavenging we have plenty of documentation around this.

http://technet.microsoft.com/en-us/library/cc759204(WS.10).aspx

Windows Server 2012 DNS PowerShell cmdlets

http://technet.microsoft.com/en-us/library/jj649850.aspx

 

Greg

dnsexport.csv