> For the complete documentation index, see [llms.txt](https://help.proxidize.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.proxidize.com/legacy-products/proxy-builder/advanced-configuration/local-ip-reservation-dhcp.md). # Local IP Reservation (DHCP) Learn how to reserve the local IP address of your Proxidize server so it does not change after a router lease renewal or server reboot. ### What Is DHCP? DHCP stands for **Dynamic Host Configuration Protocol**. It is the process your router uses to automatically assign local IP addresses to devices on your network. For example, when your Proxidize server connects to the router, the router may assign it a private IP address like: ``` 192.168.1.25 ``` This IP address is used for local access and for router rules such as port forwarding. *** ### Why Reserve the Proxidize Server IP? By default, the router may assign the Proxidize server a local IP address for a limited lease time. #### That IP address can change when: * The Proxidize server reboots. * The router reboots. * The DHCP lease expires. * The server is disconnected and reconnects later. * Another device receives the old IP address first. If the server's local IP changes, any port forwarding rules pointing to the old IP may stop working. This matters for more than dashboard access. If your Proxy Builder platform is configured to run locally instead of through the Cloud Dashboard, the generated proxies also depend on the Proxidize server's reachable host and forwarded proxy ports. Example: | Before IP Change | After IP Change | | -------------------------------------- | -------------------------------------------------------------------------- | | Port forwarding points to 192.168.1.25 | Proxidize server changes to 192.168.1.40 | | Remote access and proxy access work | Remote dashboard and generated proxy access fail until the rule is updated | DHCP reservation prevents this by telling the router to always assign the same local IP address to the Proxidize server. *** ### DHCP Reservation vs Static IP | Method | Where It Is Configured | Recommended? | | ----------------------- | ---------------------------------------- | --------------------------------------- | | DHCP reservation | On the router | Yes | | Static IP on the server | On the Proxidize server operating system | Only if instructed by Proxidize Support | We recommend using **DHCP reservation on the router** because it keeps IP management centralized and reduces the chance of IP conflicts. *** ### Before You Start You will need: * Access to the router settings page. * The Proxidize server's current private IP address. * The Proxidize server's MAC address. * Router admin username and password. If you are not sure how to access the router settings page, see [Understanding Public IPs, Private IPs, and Your Router IP Address](/legacy-products/proxy-builder/advanced-configuration/understanding-public-ips-private-ips-and-your-router-ip-address.md). {% stepper %} {% step %} ## Find the Proxidize Server's Current IP Address If you have access to the Proxidize server terminal, run: ``` ip route ``` Look for the `src` value in the active network route. Example: ``` 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.25 ``` In this example, the Proxidize server's current private IP address is: ``` 192.168.1.25 ``` You can also check the router's connected devices, clients, or DHCP clients list to find the Proxidize server. {% endstep %} {% step %} ## Find the Proxidize Server's MAC Address On the Proxidize server, run: ``` ip link ``` Look for the active network interface, such as `eth0`, `eno1`, or another Ethernet interface. The MAC address appears after `link/ether`. Example: ``` link/ether 2c:cf:67:12:34:56 ``` You can also find the MAC address in the router's connected devices or DHCP clients list. {% endstep %} {% step %} ## Reserve the IP Address on Your Router {% hint style="info" %} **Note:** The exact menu names vary by router, but the general process is similar. {% endhint %} 1. Log in to your router settings page. 2. Find the DHCP settings.\ Depending on the router, this may be under: * **Network > DHCP Server** * **LAN > DHCP** * **Advanced > Network > DHCP Server** * **Address Reservation** * **Static Lease** 3. Open the **Address Reservation**, **Static Lease**, or **Reserved IP** section. 4. Add a new reservation. 5. Enter the Proxidize server details: | Field | What to Enter | | ------------------- | --------------------------------------------- | | Device name | Proxidize Server or another recognizable name | | MAC address | The Proxidize server's MAC address | | Reserved IP address | The local IP you want the server to keep | | Status | Enabled | 6. Save or apply the configuration. 7. Reboot the Proxidize server or disconnect and reconnect its Ethernet cable so it receives the reserved IP again. Some routers may also require a router reboot before the reservation takes effect. {% endstep %} {% step %} ## TP-Link Example If you are using a TP-Link router, the DHCP reservation menu is commonly located under: ``` Advanced > Network > DHCP Server > Address Reservation ``` From there: 1. Click **Add** or **Add Reservation**. 2. Enter the Proxidize server's MAC address. 3. Enter the reserved IP address. 4. Enable the rule. 5. Save the configuration. {% endstep %} {% step %} ## Confirm the Reservation Worked After saving the reservation: 1. Reboot the Proxidize server. 2. Wait for it to reconnect to the network. 3. Check the server's IP address again. 4. Confirm it received the reserved IP address. If the server receives the same IP after rebooting, the reservation is working. {% endstep %} {% endstepper %} ### Important Notes {% hint style="warning" %} * Reserve an IP address inside the router's LAN subnet. * Avoid using an IP address that is already assigned to another device. * Some routers only allow reservations for devices currently connected to the network. * If you change the router or reset it, you may need to recreate the reservation. * If your Proxidize server has more than one network adapter, reserve the MAC address for the adapter connected to the router. {% endhint %} *** ### Why This Matters for Port Forwarding and Generated Proxies Port forwarding rules usually point to a specific private IP address. If your Proxidize server IP changes, the router may continue forwarding traffic to the old IP address. For this reason, you should reserve the Proxidize server's local IP before configuring port forwarding. This is especially important if your Proxy Builder setup is used locally. In that setup, generated proxies need: * A **host**, which is usually your public IP address or DDNS hostname. * A **port**, which must be forwarded by the router to the Proxidize server. * A stable **internal destination**, which is the Proxidize server's reserved local IP address. If the server's local IP changes, the proxy host and port may still look correct, but the router may forward traffic to the wrong internal device. For port forwarding steps, see [Port Forwarding and Triggering](/legacy-products/proxy-builder/advanced-configuration/port-forwarding-and-triggering.md). *** ### Troubleshooting | Issue | What to Check | | -------------------------------------------------- | -------------------------------------------------------------------------------------- | | The server received a different IP | Reboot the server after saving the reservation and confirm the MAC address is correct. | | The router says the IP is already in use | Choose another IP or disconnect the device currently using that address. | | The Proxidize server is not listed in DHCP clients | Make sure the server is connected to the router and online. | | Port forwarding still does not work | Confirm the forwarding rule points to the reserved IP address. | | Generated proxies do not connect remotely | Confirm the proxy ports are forwarded to the Proxidize server's reserved local IP. | | The MAC address changed | Check whether the server is using a different Ethernet adapter or USB network adapter. | *** ### Related Articles * [Understanding Public IPs, Private IPs, and Your Router IP Address](/legacy-products/proxy-builder/advanced-configuration/understanding-public-ips-private-ips-and-your-router-ip-address.md) * [Port Forwarding and Triggering](/legacy-products/proxy-builder/advanced-configuration/port-forwarding-and-triggering.md) * [Dynamic Public/WAN Addresses](/legacy-products/proxy-builder/advanced-configuration/dynamic-public-wan-addresses.md) --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://help.proxidize.com/legacy-products/proxy-builder/advanced-configuration/local-ip-reservation-dhcp.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.