It often happens that a second router is installed in a home, but it's idle, and the number of ports on the primary device is limited. Instead of buying new equipment, you can use the existing device to expand your local network. This allows you to connect more wired devices, such as game consoles, TVs, or computers, to a single infrastructure.
Usage router in switch mode — is a cost-effective and technically sound solution. It helps avoid purchasing expensive active equipment if the primary goal is simply to increase the number of available LAN ports. In this article, we'll discuss how to properly configure the equipment to avoid IP address conflicts and ensure stable operation of all connected devices.
What is the difference between a router and a switch?
To understand the principle of equipment repurposing, it's necessary to clearly understand the architectural differences between these devices. A router is a smart device that manages data flows between your local network and the global internet, assigning addresses and ensuring security. A switch, on the other hand, operates at a lower level, simply forwarding data packets between devices within the same network without any routing.
When you connect a second router as a switch, you are effectively disabling its router functionality. NAT Network Address Translation (NAT) stops working, and the device begins to act as a transparent bridge. This simplifies the network topology, making all devices visible to each other without creating subnets.
⚠️ Warning: If configured incorrectly, such as leaving the DHCP server enabled on the second device, the entire network may stop working due to an address conflict.
The key point here is operating modeIf you leave the factory settings, the router will attempt to create its own subnet, resulting in double NAT. This often causes problems with online gaming, torrents, and access to network printers. Therefore, reconfiguration is essential.
Necessary conditions and equipment preparation
Before you begin, make sure you have access to the web interfaces of both devices. You'll need a computer or laptop with a network card for the initial setup. It's also important to know the IP addresses used on your primary network to avoid any overlaps.
Connect the computer and the router being reconfigured directly with a patch cord. Do not connect this device to the ISP's main network or the main router yet. Isolation will allow you to safely change settings without risking network disruption.
☑️ Preparing for reconfiguration
It's important to reset the secondary router to factory settings if you don't remember the admin password or don't know what changes were made previously. This can be done using the button Reset on the body, which must be held for about 10-15 seconds when the power is on.
Why do you need to reset the settings?
A reset ensures that the device's memory is clear of any old routing rules, static IP addresses, or DNS servers that could conflict with the switch's new role. This is the cleanest possible start for reconfiguration.
Step-by-step instructions for setting up a router
The process of turning a router into a switch consists of several critical steps. First, you need to change the IP address of the device itself. If your main router's address 192.168.0.1, then the second one needs to be given an address from the same subnet, but not the same as the main one, for example 192.168.0.2 or 192.168.0.254.
The second and most important step is to disable the DHCP server. Find the section in the menu LAN or Local area network and uncheck the box Enable DHCP ServerThis action will transfer the address distribution function to the main router, which is necessary for the correct operation of the unified network.
| Parameter | Main router | Second router (as a switch) | Action |
|---|---|---|---|
| IP address | 192.168.1.1 | 192.168.1.2 | Change to static |
| DHCP Server | On | Turned off | Be sure to disable it |
| Wi-Fi network | Active | Disabled | It is recommended to turn it off |
| Connecting the cable | LAN port | LAN port | Use LAN-LAN |
After changing the settings, the device may prompt you to reboot. Be sure to do so for the changes to take effect. After this, your router is technically no longer a router and becomes a regular switch with ports.
Physical cable connection diagram
There's a common misconception about which port to plug the cable into. When using a router as a switch, the cable from the main device should be plugged into LAN port (usually yellow), rather than the WAN port (blue or gray). In this mode, the WAN port is ignored or operates differently, which may result in a loss of connection.
Connect any free LAN port on the primary router to any LAN port on the reconfigured device. This expands the number of available ports. All devices connected to the second router will receive IP addresses from the first.
If you want to use Wi-Fi as well (access point mode), configure your wireless network settings before disabling DHCP. Set the network name (SSID) and password. You can set the same name as your main network for seamless roaming, but it's best to use different channels to avoid interference.
⚠️ Note: Firmware interfaces may vary. Look for the "Operating Mode," "Operating Mode," or "Bridge Mode" sections—some modern models (such as Keenetic or ASUS) have an automatic switch that automatically disables DHCP and changes the port logic.
Setting up a wireless network in bridge mode
Using an old router as an access point (AP) is a great way to improve Wi-Fi coverage. Unlike repeater mode, which cuts speed in half, a wired connection to a second router provides full channel throughput.
Configure security settings. Use the standard WPA2-PSK or WPA3, if the equipment supports it. Encryption WEP It is long outdated and does not provide any protection, so its use is unacceptable in modern conditions.
To create a single namespace (seamless roaming), set the network name (SSID) and password on the second device to be exactly the same as the first. However, the broadcast channels must be different. For example, if the main router broadcasts on channel 1, set the second device to channel 6 or 11.
Possible problems and solutions
After setup, devices may not see each other or have no internet access. Most often, the issue lies with the DNS cache or IP addresses. Try updating the network configuration on the client device or rebooting it.
If you have lost access to the web interface of the second router, use the IP address you assigned to it (for example, 192.168.1.2). If you forgot which one, the reset button will help. Reset, after which the device will return to the factory IP indicated on the sticker.
Data transfer speed may be limited by the device's ports. If your old router has ports Fast Ethernet (100 Mbps), then even with gigabit internet, the speed will be limited to 100 megabits. This is a physical limitation of the equipment.
Why is the speed below 100 Mbps?
If the twisted pair cable has fewer than 8 conductors (4 conductors are used), the connection is automatically limited to 100 Mbps. For gigabit speeds, an 8-conductor Cat5e cable or higher is required.
Frequently Asked Questions
Is it possible to connect two routers with a cable via the WAN port?
It's possible, but this will create double NAT (double routing). The devices will be on different subnets, which can cause problems with port forwarding, online gaming, and access to shared resources. It's better to use a LAN-to-LAN connection with DHCP disabled.
Should I turn off Wi-Fi on the second router?
No, it's not necessary. If you need to extend your wireless network's coverage, leave Wi-Fi enabled. If you're using a router for its ports, it's best to turn Wi-Fi off to reduce electromagnetic noise and save power.
Will IPTV work through such a switch?
Yes, it will. Since the device operates as a transparent bridge (switch), it transmits multicast IPTV traffic just like a regular switch. The main requirement is that the main router is properly configured to work with the IPTV provider.
What to do if the IP addresses of the primary and secondary routers are the same?
An address conflict will occur, and the network will stop working. Before connecting the secondary router to the primary network, be sure to change its LAN IP to a free address in the same subnet by connecting to it directly from your computer.