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?)
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.
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
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.
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
Guy Recommends: A Free Trial of the Network Performance Monitor
(NPM)
Solarwinds'
Orion performance monitor
will help you discover what's happening on your network. This
utility will also guide you through troubleshooting; the dashboard will
indicate whether the root cause is a broken link, faulty equipment or
resource overload.
Perhaps the NPM's best feature is the way it suggests solutions to network
problems. Its
second best feature is the ability to monitor the health of individual VMWare
virtual machines. If you are interested in troubleshooting, and creating network maps, then I recommend that you take advantage of Solarwinds' offer.
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
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
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:
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
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:
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:
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
Syslog messages are full of information for troubleshooting network problems.
When something goes wrong then surely there will be an error message in the syslog datagram - if only we can find
that record and interpret the event. What will help to capture and analyze such
network messages is the Kiwi Syslog Server.
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.
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Guy Recommends: Orion's NPM - Network Performance Monitor
Orion's performance monitor is designed for detecting network outages. NPM makes it easy to see what's working, and what needs your attention.
This utility guides you through creating network maps. It also helps troubleshooting by indicating whether the root cause is faulty equipment, or resource overload.
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.
