Enable Remote SIP Access on Headquarter PBX

With Linkus Cloud Service Pro (LCS Pro) subscribed on Headquarter PBX, the branch office PBXs can register to the Headquarter PBX using the dedicated domain name (FQDN) of Headquarter PBX. In this way, you can free from the complicated port forwarding and enjoy private and secure remote SIP access.


  • The version of Yeastar S-Series VoIP PBX is or later.
  • You have subscribed Linkus Cloud Service Pro (LCS Pro) service.


  1. Log in to PBX web interface, go to Linkus > Linkus Server Settings > Linkus Cloud Service Pro.
  2. Select the checkboxes of Enable Linkus Server, Enable Linkus Cloud Service Pro, and Enable Remote SIP Service, which allow you to connect branch office PBXs to headquarter PBX remotely.

  3. Enable remote registration for Multisite Interconnection.
    1. On the Feature section, click .

    2. In the pop-up window, select the checkbox of Enable Multisite Interconnect Domain Register.
    3. Optional: Select the checkbox of Enable IP Restriction, and add at least one permitted IP address and subnet mask.
      Only the permitted IP address(es) can access Remote SIP Service.
      Note: This option has higher priority than any other defense rules on the system. If the permitted IP address(es) is blocked by other system defense rules, the IP address can still access the service.
    4. Click Save.
  4. Click Apply.


A dedicated domain name (FQDN) is generated, which is composed of the PBX SN and a fixed suffix lcspro.uccpbx.com. You can now use the domain name to register branch office PBXs to the headquarter PBX.