Windows 2k12 r2 DNS Speed issue

We had 2 AD servers at our primary location. Running Win2k3 AD and DNS and one DHCP.

We decided to upgrade the AD and DNS servers to WIN2K12 r2. Everything was up and running well with 4 servers 2(old) and 2(new).

Then I altered the DHCP to use the DNS of the new servers running WIN2K12. When this happened the resolve time for clients increased on average to 4 to 5 seconds.

Thankfully I only demoted one of the older servers running Windows Server 2k3. I added the last remaining 2k3 server back into the DHCP and this sped up the clients but the problem of Windows 2k12 is still an issue that needs to be resolved.

I have been using DNS Benchmark from Steve Gibson to see the differences in time compared to my older server and servers online
 Final benchmark results, sorted by nameserver performance:
 (average cached name retrieval speed, fastest to slowest)

   10.  1.  1. 11 |  Min  |  Avg  |  Max  |Std.Dev|Reliab%|
  ----------------+-------+-------+-------+-------+-------+
  + Cached Name   | 0.000 | 0.000 | 0.002 | 0.000 | 100.0 |
  + Uncached Name | 0.015 | 0.079 | 0.238 | 0.066 | 100.0 |
  + DotCom Lookup | 0.023 | 0.073 | 0.115 | 0.033 | 100.0 |
  ---<-------->---+-------+-------+-------+-------+-------+
                           DC4
                Local Network Nameserver


   10.  1.  1.  3 |  Min  |  Avg  |  Max  |Std.Dev|Reliab%|
  ----------------+-------+-------+-------+-------+-------+
  + Cached Name   | 0.000 | 0.000 | 0.000 | 0.000 | 100.0 |
  + Uncached Name | 3.552 | 4.138 | 8.085 | 0.758 |  97.8 |
  + DotCom Lookup | 3.461 | 3.888 | 4.596 | 0.404 |  97.7 |
  ---<-------->---+-------+-------+-------+-------+-------+
                       WIN2K12-AD1
                Local Network Nameserver


    8.  8.  8.  8 |  Min  |  Avg  |  Max  |Std.Dev|Reliab%|
  ----------------+-------+-------+-------+-------+-------+
  - Cached Name   | 0.004 | 0.004 | 0.006 | 0.000 | 100.0 |
  - Uncached Name | 0.030 | 0.072 | 0.340 | 0.059 | 100.0 |
  - DotCom Lookup | 0.040 | 0.079 | 0.153 | 0.042 | 100.0 |
  ---<-------->---+-------+-------+-------+-------+-------+
             google-public-dns-a.google.com
                 GOOGLE - Google Inc.,US


    8.  8.  4.  4 |  Min  |  Avg  |  Max  |Std.Dev|Reliab%|
  ----------------+-------+-------+-------+-------+-------+
  - Cached Name   | 0.004 | 0.004 | 0.005 | 0.000 | 100.0 |
  - Uncached Name | 0.030 | 0.077 | 0.322 | 0.062 | 100.0 |
  - DotCom Lookup | 0.040 | 0.076 | 0.164 | 0.041 | 100.0 |
  ---<-------->---+-------+-------+-------+-------+-------+
             google-public-dns-b.google.com
                 GOOGLE - Google Inc.,US


   10.  1.  1.  5 |  Min  |  Avg  |  Max  |Std.Dev|Reliab%|
  ----------------+-------+-------+-------+-------+-------+
  + Cached Name   | 0.000 | 0.006 | 0.254 | 0.039 | 100.0 |
  + Uncached Name | 3.474 | 4.332 | 8.175 | 1.316 |  97.7 |
  + DotCom Lookup | 3.470 | 4.043 | 4.660 | 0.448 |  97.6 |
  ---<-------->---+-------+-------+-------+-------+-------+
                       WIN2K12-AD2
                Local Network Nameserver

I did not post all the servers less than this. I think its pretty sad performance when google can out resolve your local DNS. Also WIN2k3 out preforms Win2k12.

There must be something in the config that is not right. This kind of slowness is not normal.

If anyone can help that would be great.

Thanks :)
crawforditAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

ZenVenkyArchitectCommented:
I suggest you to configure DNS settings as per the link below, so that the DNS communication works fine.

DNS Best Practices
1
crawforditAuthor Commented:
Those are really good practices. I just learned during my troubleshooting to enable IPV6. Which was done and it was nice to see it listed here. I did go through the list and still the servers are not benching the way they should.

I should also mention these servers are VMware hosts as well. But all the AD servers are VM. Just thought I would add to make a clearer picture.
0
footechCommented:
I've read that some routers or other networking equipment will drop packets that have a ECN bit set.  Server 2012 has ECN turned on by default.  Run the following to show current status.
netsh interface tcp show global

Open in new window


If ECN Capability is enabled, you can run the following to disable it: (no reboot required)
netsh interface tcp set global ecncapability=disabled

Open in new window

0
Introducing the "443 Security Simplified" Podcast

This new podcast puts you inside the minds of leading white-hat hackers and security researchers. Hosts Marc Laliberte and Corey Nachreiner turn complex security concepts into easily understood and actionable insights on the latest cyber security headlines and trends.

crawforditAuthor Commented:
Thanks footech for the suggestion. We run a switched network and no routers from our clients that have issues. I tried it anyway with no change in symptoms.
0
footechCommented:
Sorry, can't think of anything else.  You may want to request attention to see if others might chime in.
1
crawforditAuthor Commented:
TEST: Forwarders/Root hints (Forw)
                  Error: All forwarders in the forwarder list are invalid.

         Summary of test results for DNS servers used by the above domain
         controllers:

            DNS server: 10.1.1.7 (<name unavailable>)
               1 test failure on this DNS server
               PTR record query for the 1.0.0.127.in-addr.arpa. failed on the DNS server 10.1.1.7

I ran dcdiag /test:DNS with this result. Now this DNS server is not active anymore. I ran ipconfig /flushdns and ipconfig/registerdns. Still the same result. How do I get is of this record. I looked in the DNS tool but there is no listing.
0
footechCommented:
To adjust forwarders, go to the properties of the server in the DNS Management console.  There's a "forwarders" tab.
1

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
crawforditAuthor Commented:
I adjusted the forwarders to reflect each of the new dns servers with no improvement in speed. I then added 8.8.8.8 to each dns server and then the dns speed took off. Looks like they needed some outside servers to forward lookup info too.
0
crawforditAuthor Commented:
I've requested that this question be closed as follows:

Accepted answer: 0 points for crawfordit's comment #a41314148

for the following reason:

... done
0
crawforditAuthor Commented:
..
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
DNS

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.