Computer Performance, Windows Server 2003

 

DNSLint in Windows Server 2003

DNSLint troubleshooting Utility for DNS

I am always on the lookout for a good new Microsoft utility.  DNSLint is my current favourite.

For basic connectivity errors you cannot beat Ping and Ipconfig.  But what if they don't solve the problem?  The answer is try DNSLint.

Topics for DNSLint

Displays port numbers - htm output

Firewall problems plague me, so my killer feature of DNSLint is that it displays port numbers e.g. TCP 53.  As a bonus it displays the information as HTML.  Perhaps this is the start of a new trend by Microsoft to replace the DOS output of command line utilities is permanent files.  (Who remembers to pipe the output of Ipconfig to a text file?)

Where does DNSLint come from?

The first question that I ask about any utility is where do you find it?  In the case of DNSLint the answer is: Support Cabinet on Windows Server 2003 CD.

By accident if discovered that to get the most out of DNSLint I needed the a reverse lookup zone.  I say by accident as I normally set up a reverse lookup zone as best practice.  But I went to a customers site and got egg on my face when DNSLint would not display correctly.  I blamed the customer - but only under my breath!

Does DNSLint work with Windows 2000?  Yes just provided you have access to the Windows Server 2003 CD.


TrainSignal - Recommended Training VideosDNS is a huge topic, as an MCT trainer, I can thoroughly recommend TrainSignal because they provide practical hands on training.  In particular, I like the way TrainSignal cover all learning methods, instructor lead, video and of course text material.  You can either take one module, for example DNS or go for a combination of modules.  Learn more about DNS 2003 here


Getting started with DNSLint - /d /s

As with many of Windows 2003's command line utilities there are whole bank of switches.  To get started try DNSLint /d yourdom.com.  However there is a trap with /d,  if you are NOT connected to the internet.  You must add another switch:  /s server IP.  Technically /s avoids the timeout when DNSLint tries to contact InterNIC whois

Example go to the command line type:  DNSLint /d yourdom.net  /s 10.1.0.50

DNSLint tips for DNS in Windows 2003 The second and subsequent times you run DNSLint,  append the /y switch, meaning overwrite the dnslint.htm file.  Even better use the /r and specify your own filename.  For example, /r serverx.htm, or /t if you prefer a text file.

Troubleshooting Email with DNSLint - /c

Another feature of DNSLint is that it displays MX records which will assist in tracking down email delivery problems.  For further email testing, for example SMTP or POP3, try the /c switch.  It is possible this only works if the ports are the defaults, 25 SMTP and 110 POP.

To be clear if you just want to test SMTP the command would be:
DNSLint /d guybay.com /c smtp

Checking Active Directory - /ad

To tell the truth I was disappointed with this /ad switch.  To be fair it is only designed to troubleshoot forest replication.  However I was hoping for a list of _gc or _dc records.  I even tried the /v (Verbose) mode - but no dice, just the bare bones of the Glue record for Active Directory Forest replication

DNS Sample report

DNSLint Report
System Date: Wed Jan 26 09:47:25 2005

Command run:
dnslint /d computerperformance.co.uk  /s 10.1.0.20

Domain name tested:
computerperformance.co.uk

The following 4 DNS servers were identified as authoritative for the domain:
DNS server: dns1.cp.computerperformance.co.uk

IP Address: 10.1.0.20
Responding to queries: YES
UDP port 53 responding to queries: YES
TCP port 53 responding to queries: Not tested
Answering authoritatively for domain: YES

SOA record data from server:
Authoritative name server: dns.cp.computerperformance.co.uk
Hostmaster: msnhst.computerperformance.co.uk
Zone serial number: 54234
Zone expires in: 83.33 day(s)
Refresh period: 900 seconds
Retry delay: 600 seconds
Default (minimum) TTL: 7200 seconds

Additional authoritative (NS) records from server:
dns1.cp.computerperformance.co.uk 10.1.0.20
dns1.dc.computerperformance.co.uk 10.68.128.151
dns1.sj.computerperformance.co.uk 10.1.97.11
dns1.uk.computerperformance.co.uk 10.1.232.37

Host (A) records for domain from server:
10.1.197.100
10.1.197.102
10.1.230.218
10.1.230.219
10.1.230.220

Mail Exchange (MX) records from server (preference/name/IP address):
10 maila.computerperformance.co.uk 10.107.3.124
10 mailb.computerperformance.co.uk 10.107.3.122
10 mailc.computerperformance.co.uk 10.107.3.126

-----------------------------------------------------------------------

DNS server: dns1.uk.computerperformance.co.uk

IP Address: 10.1.232.37
Responding to queries: YES
Answering authoritatively for domain: YES

SOA record data from server:
Authoritative name server: dns.cp.computerperformance.co.uk
Hostmaster: msnhst.computerperformance.co.uk
Zone serial number: 54234
Zone expires in: 83.33 day(s)
Refresh period: 900 seconds
Retry delay: 600 seconds
Default (minimum) TTL: 7200 seconds

Additional authoritative (NS) records from server:

dns1.cp.computerperformance.co.uk 10.1.0.20
dns1.dc.computerperformance.co.uk 10.68.128.151
dns1.sj.computerperformance.co.uk 10.1.97.11
dns1.uk.computerperformance.co.uk 10.1.232.37

Host (A) records for domain from server:
10.1.230.219
10.1.230.220
10.1.197.100
10.1.197.102
10.1.230.218


Mail Exchange (MX) records from server (preference/name/IP address):
10 maila.computerperformance.co.uk 10.107.3.124
10 mailb.computerperformance.co.uk 10.107.3.122
10 mailc.computerperformance.co.uk 10.107.3.126

----------------------------------------------------------------------

DNS server: dns1.dc.computerperformance.co.uk

IP Address: 10.68.128.151
Responding to queries: YES
Answering authoritatively for domain: YES

SOA record data from server:
Authoritative name server: dns.cp.computerperformance.co.uk
Hostmaster: msnhst.computerperformance.co.uk
Zone serial number: 54234
Zone expires in: 83.33 day(s)
Refresh period: 900 seconds
Retry delay: 600 seconds
Default (minimum) TTL: 7200 seconds

Additional authoritative (NS) records from server:

dns1.cp.computerperformance.co.uk 10.1.0.20
dns1.dc.computerperformance.co.uk 10.68.128.151
dns1.sj.computerperformance.co.uk 10.1.97.11
dns1.uk.computerperformance.co.uk 10.1.232.37


Host (A) records for domain from server:
10.1.230.218
10.1.230.219
10.1.230.220
10.1.197.100
10.1.197.102

Mail Exchange (MX) records from server (preference/name/IP address):
10 maila.computerperformance.co.uk 10.107.3.124
10 mailb.computerperformance.co.uk 10.107.3.122
10 mailc.computerperformance.co.uk 10.107.3.126

----------------------------------------------------------------------

DNS server: dns1.sj.computerperformance.co.uk
IP Address: 10.1.97.11
Responding to queries: YES

Answering authoritatively for domain: YES
SOA record data from server:
Authoritative name server: dns.cp.computerperformance.co.uk
Hostmaster: msnhst.computerperformance.co.uk
Zone serial number: 54234
Zone expires in: 83.33 day(s)
Refresh period: 900 seconds
Retry delay: 600 seconds
Default (minimum) TTL: 7200 seconds

Additional authoritative (NS) records from server:

dns1.cp.computerperformance.co.uk 10.1.0.20
dns1.dc.computerperformance.co.uk 10.68.128.151
dns1.sj.computerperformance.co.uk 10.1.97.11
dns1.uk.computerperformance.co.uk 10.1.232.37


Host (A) records for domain from server:
10.1.197.100
10.1.197.102
10.1.230.218

Mail Exchange (MX) records from server (preference/name/IP address):
10 maila.computerperformance.co.uk 10.107.3.124
10 mailb.computerperformance.co.uk 10.107.3.122
10 mailc.computerperformance.co.uk 10.107.3.126

-----------------------------------------------------------------------

Legend: warning, error

DNSLint developed by Tim Rains

-

Summary

Do you have a problem with DNS? Investigate solutions with DNSLint.  Not only will you get a friendly HTML output, but it will display port numbers and Glue records for Active Directory replication.

Related DNS Server topics

 *


Google

Webcomputerperformance.co.uk

GFi Events Manager

Guy Recommends: GFi EventsManager

Here is a solution to monitor, manage and archive thousands of events that are generated by devices across your entire network.  Get your free evaluation copy of GFI EventsManager.

 

Home Copyright © 1999-2008 Computer Performance LTD All rights reserved

Please report a broken link, or an error.