--- title: How to configure a Grandstream GXW VoIP Gateway with a 3CX Phone System description: Help Center --- [Skip to content](https://help.voipsupply.com/migration/en/knowledge/how-to-configure-a-grandstream-gxw-voip-gateway-with-3cx-phone-system#main-content) English Show submenu for translations ![voipsupply.com\_logo450.jpg\]](https://help.voipsupply.com/hs-fs/hubfs/voipsupply.com_logo450.jpg?height=40&name=voipsupply.com_logo450.jpg) - [Shop](http://www.voipsupply.com/) - [Contact Us](https://www.voipsupply.com/contact-voipsupply) - [Blog](http://www.voipsupply.com/blog/voip-insider/) - [Support](https://www.voipsupply.com/getsupport) Open main navigation Close main navigation - [Shop](http://www.voipsupply.com/) - [Contact Us](https://www.voipsupply.com/contact-voipsupply) - [Blog](http://www.voipsupply.com/blog/voip-insider/) - [Support](https://www.voipsupply.com/getsupport) - English Show submenu for translations - [Contact us](https://www.voipsupply.com/contact-voipsupply) [Contact us](https://www.voipsupply.com/contact-voipsupply) This is a search field with an auto-suggest feature attached. - There are no suggestions because the search field is empty. 1. [Help Center](https://help.voipsupply.com/migration/en/knowledge?hsLang=en) # How to configure a Grandstream GXW VoIP Gateway with a 3CX Phone System Setting up Grandstream GXW gateways with a 3CX SBC for multiple locations is an officially unsupported configuration, but it can be made to work by directing the gateway's registration to the SBC. A 3CX SBC acts as a tunnel, allowing remote devices to connect to a hosted 3CX instance by combining SIP and RTP traffic to pass through firewalls.  This guide assumes you have a hosted 3CX PBX and an SBC deployed at each remote site.  High-level overview Deploy a 3CX Session Border Controller (SBC) at each remote location In 3CX, add each Grandstream GXW as a VoIP Gateway, using the local IP of its site's SBC as the registrar. Configure each GXW gateway to point to the local SBC's IP address. Optionally, use a VPN to connect sites for a fully supported configuration.  Detailed steps for each remote site Step 1: Install and configure the 3CX SBC First, ensure you have a 3CX SBC running at each remote location where a GXW gateway will be installed. - Select hardware: You can use a dedicated PC, a Virtual Machine, or a Raspberry Pi to run the SBC software. - Install SBC: Follow the official 3CX installation guide for the SBC. It will create a tunnel between the remote network and your 3CX PBX. Step 2: Configure the Grandstream GXW in the 3CX Management Console - Log in to your 3CX Management Console. - Navigate to SIP Trunks \> Add Gateway. - Select Grandstream as the brand and choose your GXW model (e.g., GXW-4224 for FXS or GXW-4104 for FXO). - In the gateway's settings, find the Registrar or Proxy field. Do not enter the main 3CX FQDN. Instead, enter the internal IP address of the SBC at that specific remote location. - Set up the PSTN lines and DID rules as needed for inbound calls. - For FXS gateways, select the extensions that will be using the analog ports on the gateway. - Click OK to save the gateway configuration. Step 3: Prepare and configure the Grandstream GXW - Perform a factory reset on the Grandstream GXW. - Log in to the gateway's web interface using its local IP address. - Navigate to the Account settings for the gateway (for GXW-42XX FXS gateways, this will be under FXS Ports). - In the account's SIP Server field, enter the local IP address of the SBC. - Use the SIP credentials generated by 3CX. You will find these in the gateway configuration within the 3CX Management Console. - Ensure that each gateway's internal settings reflect the 3CX configuration. The most critical step is ensuring the gateway registers to the local SBC IP, not the 3CX server directly. Step 4: Validate and test the setup - After configuring the gateway and SBC at a remote site, test the connection to confirm it is working properly. - Check the SIP Trunks page in the 3CX Management Console to ensure the gateway's status shows as connected. - If you have an FXS gateway, plug an analog phone into a port and test internal calls to other 3CX extensions. - Test inbound and outbound calls through the gateway's PSTN lines (if using an FXO model). Alternative: Use a site-to-site VPN The officially supported method for connecting a remote gateway is via a site-to-site VPN. Setup: Establish a VPN tunnel between each remote site's network and your main 3CX server network. Provisioning: You can then provision the Grandstream GXW gateway as if it were on the same local network as the 3CX PBX. - [Cloud Management Platforms](https://help.voipsupply.com/migration/en/knowledge/cloud-management-platforms?hsLang=en#main-content) - [Fanvil](https://help.voipsupply.com/migration/en/knowledge/cloud-management-platforms?hsLang=en#fanvil) - [SIP Paging Gateway](https://help.voipsupply.com/migration/en/knowledge/sip-paging-gateway?hsLang=en#main-content) - [Fanvil](https://help.voipsupply.com/migration/en/knowledge/sip-paging-gateway?hsLang=en#fanvil) - [Device Factory Resets](https://help.voipsupply.com/migration/en/knowledge/device-factory-resets?hsLang=en#main-content) - [Fanvil](https://help.voipsupply.com/migration/en/knowledge/device-factory-resets?hsLang=en#fanvil) - [SIP Register Configuration](https://help.voipsupply.com/migration/en/knowledge/sip-register-configuration?hsLang=en#main-content) - [Fanvil](https://help.voipsupply.com/migration/en/knowledge/sip-register-configuration?hsLang=en#fanvil) - [Provisioning Devices](https://help.voipsupply.com/migration/en/knowledge/provisioning-devices?hsLang=en#main-content) - [Grandstream GXW42XX / VoIP Gateway](https://help.voipsupply.com/migration/en/knowledge/provisioning-devices?hsLang=en#grandstream-gxw42xx-voip-gateway) - [Broadcast / Multicast](https://help.voipsupply.com/migration/en/knowledge/broadcast-multicast?hsLang=en#main-content) - [Fanvil](https://help.voipsupply.com/migration/en/knowledge/broadcast-multicast?hsLang=en#fanvil) - [Device / Network Configuration](https://help.voipsupply.com/migration/en/knowledge/device-network-configuration?hsLang=en#main-content) - [Fanvil](https://help.voipsupply.com/migration/en/knowledge/device-network-configuration?hsLang=en#fanvil) - [Grandstream](https://help.voipsupply.com/migration/en/knowledge/device-network-configuration?hsLang=en#grandstream) - [Yeastar PBX](https://help.voipsupply.com/migration/en/knowledge/device-network-configuration?hsLang=en#yeastar-pbx) - [Poly / HP](https://help.voipsupply.com/migration/en/knowledge/device-network-configuration?hsLang=en#poly-hp) - [Network Troubleshooting](https://help.voipsupply.com/migration/en/knowledge/network-troubleshooting?hsLang=en#main-content) - [Yeastar PBX](https://help.voipsupply.com/migration/en/knowledge/network-troubleshooting?hsLang=en#yeastar-pbx) - [Backup & Restore](https://help.voipsupply.com/migration/en/knowledge/backup-restore?hsLang=en#main-content) - [Yeastar Backup & Restore](https://help.voipsupply.com/migration/en/knowledge/backup-restore?hsLang=en#yeastar-backup-restore) - [PBX Licensing](https://help.voipsupply.com/migration/en/knowledge/pbx-licensing?hsLang=en#main-content) - [Switchvox PBX](https://help.voipsupply.com/migration/en/knowledge/pbx-licensing?hsLang=en#switchvox-pbx) - [Provisioning Services](https://help.voipsupply.com/migration/en/knowledge/provisioning-services?hsLang=en) VoIP Supply Help Center Copyright © 2026, VoIP Supply