Hi Team,

In our organization we have single DNS and AD server but DNS has two zones .com and .local, We are using Skype for business 

as well.

Problem: In the IP Address (Network Adapter) If i assign Local DNS as primary, Skype for Business is not working. If i assign ISP or global IP as primary DNS . .local is not resolving or working.

Please help how both can work .local and Skype for Business.

Hi,

What are you using as your sip domain?
If you're using the .com one, you'll have to make sure you have all the required DNS records to allow automatic client sign in.

Follow this KB article to confirm you have DNS configured correctly: https://technet.microsoft.com/en-us/library/dn951397.aspx?f=255&MSPPError=-2147217396

Being able to traverse between your .com (external) and .local (internal) DNS and IPs comes down to using the Edge Server.  Many of us have set this up many times, very easy.  Your .local domain is where you will provision your SIP Server / Skype for Business Server and your .com/DMZ environment is where your Edge will be provisioned.  Your Edge Server will have to Network Interfaces, one public, one private.  Your Public NIC should have the Public IP address of your Edge and your Private NIC, the private IP address.  Your Private NIC will connect to your internal Skype for Business Standard Ed or Pool Servers.  Both networks will have proper DNS and Certificates applied and all of your configuration will be done via the Skype for Business Toplogy Builder.  The information I have provided is an extremely high level overview.  Please start with the URL https://technet.microsoft.com/en-us/library/dn933893.aspx and then Matt Landis has a good step by step guide via http://windowspbx.blogspot.com/2015/04/step-by-step-skype-for-business-server.html