You need to add SRV records if you are using Lync (Office 365). Following is the sample SRV record details that you need to add for your domain:
Record Type: SRV
TTL: 1 Hour
If you are using cPanel/WHM, you will see that there is no option in the DNS zone editor for “Service” or “Protocol” while adding SRV record.
Following is the sample record that will help you to add Lync related DNS records in cPanel/WHM: