Solved

DNS Client port range

Posted on 2006-06-25
3
364 Views
Last Modified: 2013-12-04
Hi,

I wish to implement ip filtering on all my client PCs but I'm having problems with my Win2k3 dns server as the client-side port range is massive. To quote MS:

"By default, Windows Server 2003 and Windows 2000 Server DNS servers use ephemeral client-side ports when they query other DNS servers...."

Is there any proper way to reduce the port range on the dns server to a manageable number? Is there a way it can be reduced to a single port? Is there a performance issue with implementing this?

Also, under what conditions does a dns client and server choose to use udp over tcp? Is there any way of choosing just one protocol? Which one is better?

Thanks
0
Comment
Question by:gibjon
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
3 Comments
 
LVL 12

Accepted Solution

by:
gidds99 earned 500 total points
ID: 16982632
Windows uses ephemiral ports for DNS connections as you have mentioned above.  These ports fall within the range 1024 to 5000.  You can control this range via a registry setting but it is not only limited to DNS connections (it affects all connections). Clearly if the range was limited too much this may cause problems.

Hope this helps.
0

Featured Post

Ransomware-A Revenue Bonanza for Service Providers

Ransomware – malware that gets on your customers’ computers, encrypts their data, and extorts a hefty ransom for the decryption keys – is a surging new threat.  The purpose of this eBook is to educate the reader about ransomware attacks.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Recently, I read that Microsoft has analysed statistics for their security intelligence report. It revealed: still, the clear majority of windows users do their daily work as administrator. An administrative account is a burden, security-wise. My ar…
Container Orchestration platforms empower organizations to scale their apps at an exceptional rate. This is the reason numerous innovation-driven companies are moving apps to an appropriated datacenter wide platform that empowers them to scale at a …
Monitoring a network: why having a policy is the best policy? Michael Kulchisky, MCSE, MCSA, MCP, VTSP, VSP, CCSP outlines the enormous benefits of having a policy-based approach when monitoring medium and large networks. Software utilized in this v…
Michael from AdRem Software outlines event notifications and Automatic Corrective Actions in network monitoring. Automatic Corrective Actions are scripts, which can automatically run upon discovery of a certain undesirable condition in your network.…

717 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question