{"id":4356,"date":"2013-01-08T00:01:00","date_gmt":"2013-01-08T00:01:00","guid":{"rendered":"https:\/\/blogs.technet.microsoft.com\/heyscriptingguy\/2013\/01\/08\/replace-nslookup-with-a-built-in-windows-8-powershell-function\/"},"modified":"2013-01-08T00:01:00","modified_gmt":"2013-01-08T00:01:00","slug":"replace-nslookup-with-a-built-in-windows-8-powershell-function","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/scripting\/replace-nslookup-with-a-built-in-windows-8-powershell-function\/","title":{"rendered":"Replace NSLookup with a Built-in Windows 8 PowerShell Function"},"content":{"rendered":"

Summary:<\/strong> Microsoft Scripting Guy, Ed Wilson, continues his discussion about using Windows PowerShell on Windows 8 to troubleshoot DNS issues.\nMicrosoft Scripting Guy, Ed Wilson, is here. Yesterday, I talked about using some of the functions from the DNSClient module to troubleshoot networking issues<\/a>. Specifically, I talked about looking at the configured DNS server and at the DNS client cache.\nToday, I want to continue that discussion by examining a couple of more functions.<\/p>\n

Resolving DNS names<\/h2>\n

To make a connection, I need to resolve a DNS host name to an IP address. Actually, I do not need to do this; my computer needs to do this. But if the name does not resolve correctly, then my applications do not work. Often, when traveling, a quick call to the Help desk turns into a very long and frustrating call to the Help desk, which in turn becomes the Helpless desk. Dude!\nTherefore, I need to do all the troubleshooting on my own, so I can tell the Help desk what they need to do in order to resolve my problem. An intermediate troubleshooting step is to use the old-fashioned NSLookup utility. A long time ago, I used to have a dedicated NSLookup GUI utility. But that was a long time ago. When I moved into consulting and began working on different systems, I decided I needed to learn how to use the Windows NSLookup command-line utility—because it was the only tool I could be confident would be available. Unfortunately, the old-fashioned Windows NSLookup command-line utility is not all that much fun to use.<\/p>\n

The PowerShell “NSLookup” tool<\/h2>\n

Luckily, I no longer have to use the old-fashioned command-line NSLookup tool because Windows 8, Windows Server 2012, and even the Microsoft Surface have the DNSClient module built-in. This module supplies the Resolve-DNSName<\/strong>. This function works great (despite the fact that some in the community believe it should have been named Get-DNSName<\/strong>).\nIn its most basic form, I simply type the host to resolve as an argument for Resolve-DNSName<\/strong>. This technique is shown here.<\/p>\n

Resolve-DnsName www.scriptingguys.com<\/p>\n

The command and its associated output is shown here.<\/p>\n

14:28 C:> Resolve-DnsName www.scriptingguys.com<\/p>\n

 Name                           Type   TTL   Section    NameHost<\/p>\n

—-                           —-   —   ——-    ——–<\/p>\n

www.scriptingguys.com          CNAME  3600  Answer     scriptingguys.com<\/p>\n

 Name       : scriptingguys.com<\/p>\n

QueryType  : A<\/p>\n

TTL        : 3600<\/p>\n

Section    : Answer<\/p>\n

IP4Address : 64.4.11.37<\/p>\n

  <\/p>\n

Name       : scriptingguys.com<\/p>\n

QueryType  : A<\/p>\n

TTL        : 3600<\/p>\n

Section    : Answer<\/p>\n

IP4Address : 65.55.58.201\n <\/p>\n

Name                   : scriptingguys.com<\/p>\n

QueryType              : SOA<\/p>\n

TTL                    : 3600<\/p>\n

Section                : Authority<\/p>\n

NameAdministrator      : msnhst.microsoft.com<\/p>\n

SerialNumber           : 2012050301<\/p>\n

TimeToZoneRefresh      : 1800<\/p>\n

TimeToZoneFailureRetry : 900<\/p>\n

TimeToExpiration       : 2419200<\/p>\n

DefaultTTL             : 3600<\/p>\n

 \nThe thing that is a bit interesting here is that there are three different object returned by this query. The objects are shown here.<\/p>\n

14:30 C:> Resolve-DnsName www.scriptingguys.com | gm -MemberType Properties | select<\/p>\n

 typename -Unique<\/p>\n

 TypeName<\/p>\n

——–<\/p>\n

Microsoft.DnsClient.Commands.DnsRecord_PTR<\/p>\n

Microsoft.DnsClient.Commands.DnsRecord_A<\/p>\n

Microsoft.DnsClient.Commands.DnsRecord_SOA\n \nIf I am interested in a specific record type, I query it directly by specifying the type<\/strong> <\/em>parameter, as shown here.<\/p>\n

14:34 C:> Resolve-DnsName www.scriptingguys.com -Type ptr<\/p>\n

 <\/p>\n

Name                           Type   TTL   Section    NameHost<\/p>\n

—-                           —-   —   ——-    ——–<\/p>\n

www.scriptingguys.com          CNAME  3251  Answer     scriptingguys.com<\/p>\n

 <\/p>\n

Name                   : scriptingguys.com<\/p>\n

QueryType              : SOA<\/p>\n

TTL                    : 3251<\/p>\n

Section                : Authority<\/p>\n

NameAdministrator      : msnhst.microsoft.com<\/p>\n

SerialNumber           : 2012050301<\/p>\n

TimeToZoneRefresh      : 1800<\/p>\n

TimeToZoneFailureRetry : 900<\/p>\n

TimeToExpiration       : 2419200<\/p>\n

DefaultTTL             : 3600\n Unfortunately, the type<\/strong> <\/em>parameter does not accept multiple types. It does not generate an error, but it leads to unpredictable results. If I need to examine multiple record types I type the record types as an array and send them down the pipeline through the Foreach-Object<\/strong> cmdlet. This technique is shown here.<\/p>\n

“ptr”, “a” | % {Resolve-DnsName -Name www.scriptingguys.com -Type $_}\n I can use the same technique to look up multiple DNS names. This technique appears here where I return only the CNAME records for www.microsoft.com and ftp.microsoft.com.<\/p>\n

 “www.microsoft.com”, “ftp.microsoft.com” | % {Resolve-DnsName $_ -type cname}\n If I want to check the DNS Cache for a specific record, I can query it directly by using the Resolve-DNSName<\/strong> function. If a record does not exist in cache (perhaps it timed out), an error returns, as shown here.<\/p>\n

14:41 C:> Resolve-DnsName ftp.microsoft.com -CacheOnly<\/p>\n

Resolve-DnsName : ftp.microsoft.com : DNS record does not exist<\/p>\n

At line:1 char:1<\/p>\n

+ Resolve-DnsName ftp.microsoft.com -CacheOnly<\/p>\n

+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~<\/p>\n

    + CategoryInfo          : ResourceUnavailable: (ftp.microsoft.com:String) [Reso<\/p>\n

   lve-DnsName], Win32Exception<\/p>\n

    + FullyQualifiedErrorId : RECORD_DOES_NOT_EXIST,Microsoft.DnsClient.Commands.Re<\/p>\n

   solveDnsName\n To see what my DNS server returns, I can query it directly. To do this, I have several options. For example, I can simply specify that I want to use the DNS protocol, as shown here.<\/p>\n

Resolve-DnsName ftp.microsoft.com –DnsOnly\nIf, on the other hand, the problem appears to be intermittent DNS resolution, I may want to specify a specific DNS server. First, I probably need to see how my currently configured DNS servers are set. I use the Get-DNSClientServerAddress<\/strong> function, as shown here.<\/p>\n

14:45 C:> Get-DnsClientServerAddress<\/p>\n

InterfaceAlias               Interface Address ServerAddresses<\/p>\n

————–               ——— ——- —————<\/p>\n

Local Area Connection* 14           33 IPv4    {}<\/p>\n

Local Area Connection* 14           33 IPv6    {fec0:0:0:ffff::1, fec0:0:0:ffff::…<\/p>\n

vEthernet (WirelessSwitch)          31 IPv4    {192.168.6.1, 64.134.255.2, 64.134…<\/p>\n

vEthernet (WirelessSwitch)          31 IPv6    {}<\/p>\n

isatap.owv.atl.wayport.net          44 IPv4    {192.168.6.1, 64.134.255.2, 64.134…<\/p>\n

isatap.owv.atl.wayport.net          44 IPv6    {}<\/p>\n

Local Area Connection* 12           25 IPv4    {}<\/p>\n

Local Area Connection* 12           25 IPv6    {fec0:0:0:ffff::1, fec0:0:0:ffff::…<\/p>\n

vEthernet (InternalSwitch)          19 IPv4    {192.168.3.100}<\/p>\n

vEthernet (InternalSwitch)          19 IPv6    {}<\/p>\n

isatap.{FC2087E9-6988-45E…        40 IPv4    {192.168.3.100}<\/p>\n

isatap.{FC2087E9-6988-45E…        40 IPv6    {}<\/p>\n

Loopback Pseudo-Interface 1          1 IPv4    {}<\/p>\n

Loopback Pseudo-Interface 1          1 IPv6    {fec0:0:0:ffff::1, fec0:0:0:ffff::…<\/p>\n

Teredo Tunneling Pseudo-I…        34 IPv4    {}<\/p>\n

Teredo Tunneling Pseudo-I…        34 IPv6    {}<\/p>\n

6TO4 Adapter                        39 IPv4    {}<\/p>\n

6TO4 Adapter                        39 IPv6    {}\nI can easily clean up the output by filtering only the entries that contain server addresses. This is shown here.<\/p>\n

14:46 C:> Get-DnsClientServerAddress | ? serveraddresses<\/p>\n

InterfaceAlias               Interface Address ServerAddresses<\/p>\n

————–               ——— ——- —————<\/p>\n

Local Area Connection* 14           33 IPv6    {fec0:0:0:ffff::1, fec0:0:0:ffff::…<\/p>\n

vEthernet (WirelessSwitch)          31 IPv4    {192.168.6.1, 64.134.255.2, 64.134…<\/p>\n

isatap.owv.atl.wayport.net          44 IPv4    {192.168.6.1, 64.134.255.2, 64.134…<\/p>\n

Local Area Connection* 12           25 IPv6    {fec0:0:0:ffff::1, fec0:0:0:ffff::…<\/p>\n

vEthernet (InternalSwitch)          19 IPv4    {192.168.3.100}<\/p>\n

isatap.{FC2087E9-6988-45E…        40 IPv4    {192.168.3.100}<\/p>\n

Loopback Pseudo-Interface 1          1 IPv6    {fec0:0:0:ffff::1, fec0:0:0:ffff::…\nAfter I have my listing of DNS servers, I can check them one at a time. I do this by specifying the DnsServer<\/strong> parameter and specifying that I want to use DNS, as shown here.<\/p>\n

Resolve-DnsName www.msn.com -DnsOnly -Server 192.168.6.1\nI do not have to specify an IP address for the DNS Server. For example, I can query the DNS server by host name. This technique is shown here.<\/p>\n

Resolve-DnsName www.msn.com -Server ns1.msft.net\nIf I determine I have a polluted DNS cache, I use Windows PowerShell to clear the cache. The command is shown here.<\/p>\n

Clear-DnsClientCache\nJoin me tomorrow when I will have the third article of Microsoft MVP Richard Siddaway’s Windows PowerShell workflow basics series. You can review the second<\/a> and the first<\/a> articles in that series on the Hey, Scripting Guy! Blog post.\nI invite you to follow me on Twitter<\/a> and Facebook<\/a>. If you have any questions, send email to me at scripter@microsoft.com<\/a>, or post your questions on the Official Scripting Guys Forum<\/a>. See you tomorrow. Until then, peace.\nEd Wilson, Microsoft Scripting Guy<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

Summary: Microsoft Scripting Guy, Ed Wilson, continues his discussion about using Windows PowerShell on Windows 8 to troubleshoot DNS issues. Microsoft Scripting Guy, Ed Wilson, is here. Yesterday, I talked about using some of the functions from the DNSClient module to troubleshoot networking issues. Specifically, I talked about looking at the configured DNS server and at […]<\/p>\n","protected":false},"author":596,"featured_media":87096,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[396,37,3,45],"class_list":["post-4356","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-scripting","tag-dns","tag-networking","tag-scripting-guy","tag-windows-powershell"],"acf":[],"blog_post_summary":"

Summary: Microsoft Scripting Guy, Ed Wilson, continues his discussion about using Windows PowerShell on Windows 8 to troubleshoot DNS issues. Microsoft Scripting Guy, Ed Wilson, is here. Yesterday, I talked about using some of the functions from the DNSClient module to troubleshoot networking issues. Specifically, I talked about looking at the configured DNS server and at […]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts\/4356","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/users\/596"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/comments?post=4356"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts\/4356\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/media\/87096"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/media?parent=4356"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/categories?post=4356"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/tags?post=4356"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}