Successful operation of Lync servers is heavily dependent on correctly configuring DNS. All necessary DNS records should exist and resolve to the correct locations. Verify that all servers have a host record configured in DNS. Separate web components URLs and simple URLs are not automatically entered and must be manually created by an administrator.
Use the following sample nslookup sequence within a command prompt to check the host record of the pool:
nslookup set type=a lyncdirpool1.companyabc.com
A successful query returns a name and IP address. Verify that the IP returned matches the IP addresses assigned to the servers or load balancer and that no extra, or surprise, IP addresses are returned.
To verify the SRV record required ...