MikroTik cAP XL ac Repeater Setup Without Ethernet

Setting up a MikroTik cAP XL ac as a wireless repeater without Ethernet cable requires proper configuration through the device’s wireless interface. The process involves powering the device via PoE, connecting to its temporary WiFi network, accessing the web interface, and configuring it as a repeater that connects to your main router while broadcasting its own SSID.

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Contents

• Understanding MikroTik cAP XL ac Repeater Mode
• Requirements for Wireless Repeater Setup
• Step-by-Step Configuration Process
• Mounting Instructions for cAP XL ac
• Performance Considerations and Limitations
• Troubleshooting Common Issues
• Sources
• Conclusion

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Understanding MikroTik cAP XL ac Repeater Mode

The MikroTik cAP XL ac is designed primarily as a professional access point that can operate in multiple modes, including as a wireless repeater. When configured in repeater mode, the device functions as both a client (connecting to your main WiFi network) and an access point (broadcasting its own network for your devices). This configuration eliminates the need for running an Ethernet cable to the access point location.

What makes the cAP XL ac particularly suitable for repeater applications is its dual-band capability - supporting both 2.4 GHz (b/g/n) and 5 GHz (a/n/ac) frequencies. However, it’s crucial to understand that repeater mode comes with inherent limitations: the device essentially splits its airtime between receiving signals from your main router and transmitting to connected devices, resulting in approximately half the throughput compared to a direct Ethernet connection.

The cAP XL ac comes pre-configured as an access point out of the box, which means you can immediately connect to its default WiFi network to begin the setup process. The device includes two Gigabit Ethernet ports, with the first supporting 802.3af/at PoE input and the second providing passive PoE output up to 57V, making it versatile for various deployment scenarios even when using PoE for power.

Requirements for Wireless Repeater Setup

Before proceeding with the MikroTik cAP XL ac repeater setup, ensure you have the following components and information ready:

Hardware Requirements:

• MikroTik cAP XL ac access point
• PoE injector or PoE-capable switch (12-57V DC)
• Ethernet cable (for initial setup only)
• Computer or mobile device with WiFi capability
• Mounting hardware (included with the device)

Network Requirements:

• Existing WiFi network with SSID and password
• Knowledge of your main router’s IP address (optional but helpful)
• Access to MikroTik RouterOS (either through web interface or WinBox)
• Latest RouterOS firmware (recommended for optimal performance)

Prerequisites:

• Basic understanding of WiFi networking concepts
• Experience with router configuration (as mentioned in your question)
• Access to the MikroTik device via its default credentials initially

The cAP XL ac operates on both 2.4 GHz and 5 GHz frequencies, but for repeater mode, you’ll need to decide which band to use based on your main router’s capabilities and the distance between your main router and the repeater location. Generally, 2.4 GHz offers better range but lower speeds and is more prone to interference, while 5 GHz provides higher speeds with shorter range and less interference.

One important consideration is that MikroTik repeater mode doesn’t support 802.11r/k/v fast roaming protocols, which means seamless handoff between access points may not be as smooth as with a proper CAPsMAN setup or Ethernet-connected access points. This limitation is particularly relevant if you have mobile devices frequently moving between network coverage areas.

Step-by-Step Configuration Process

Initial Connection and Access

1. Power the Device: Connect the MikroTik cAP XL ac to power using the included PoE injector or a compatible PoE switch. The device should power on within a few seconds, and you’ll typically see status LEDs indicating it’s ready for setup.

2. Connect to Default WiFi: The device broadcasts a temporary WiFi network with an SSID similar to “MikroTik-cAP-XL-ac-XXXX” (where XXXX represents part of the device’s MAC address). Connect your computer or mobile device to this network.

3. Access the Web Interface: Open a web browser and navigate to http://192.168.88.1. The device will load a QuickSet interface where you can perform initial configuration. The default login credentials are username “admin” with no password (leave password field blank).

Firmware Update (Recommended)

Before proceeding with repeater configuration, it’s best practice to update RouterOS to the latest version:

1. In the QuickSet interface, locate the “Check for updates” option
2. Follow the prompts to download and install the latest firmware
3. Once updated, the device will restart automatically

Repeater Configuration Steps

1. Access Wireless Settings: After logging in, navigate to the “Wireless” section in the left menu. You’ll see wireless interfaces for both 2.4 GHz and 5 GHz bands (typically labeled as wlan1 and wlan2).

2. Select Interface to Configure: Choose which wireless interface you want to configure as a repeater. For most applications, you’ll want to use the 5 GHz interface (wlan2) for backhaul to your main router and the 2.4 GHz interface (wlan1) for client connections, or vice versa depending on your network design.

3. Change Mode to Repeater:

• Select your chosen wireless interface
• In the “Mode” dropdown, change from “AP” to “Repeater”
• Click “Apply”

4. Configure Uplink Connection:

• Enter the SSID of your main WiFi network in the “SSID” field
• Set the frequency or leave it on “Auto” for automatic selection
• Configure the security settings to match your main router:
• Set “Authentication” to “WPA2-PSK” (or your router’s authentication method)
• Enter the exact same WPA2-PSK key/password as your main router
• Ensure “WPA Pre-shared key” matches your main network

5. Bridge Configuration:

• Go to the “Bridge” section
• Ensure your wireless interface is bridged with Eth2 (or the bridge interface that includes Eth2)
• This allows devices connected to the cAP XL ac to receive IP addresses from your main router

6. Additional Settings:

• Set a proper hostname for easy identification
• Configure system time settings if needed
• Consider adjusting the “tx-power” setting if you need to limit transmission power
• Set country code to match your location for regulatory compliance

7. Save and Apply: Click “Apply” to save all changes and restart the wireless interfaces with the new configuration.

Verification

After configuration, your MikroTik cAP XL ac should:

• Connect to your main WiFi network
• Broadcast its own WiFi network with the same SSID/password as your main network (if you want seamless roaming) or a different SSID
• Provide internet access to devices connected to it

You can verify the connection by:

• Checking the “Wireless” section for established connections
• Looking at the “Interfaces” section to confirm the bridge is active
• Connecting a test device to the repeater’s WiFi and confirming internet access

Mounting Instructions for cAP XL ac

Once your MikroTik cAP XL ac is properly configured as a repeater, you’ll want to mount it in an optimal location for WiFi coverage. The device includes versatile mounting options for different installation scenarios.

Ceiling Mount Installation

1. Mark Mounting Holes:

• Hold the mounting bracket against your ceiling in the desired location
• Mark the positions of the two mounting holes
• Drill two 4.5-5mm holes for anchors
• Insert plastic anchors into the holes

2. Attach Mounting Bracket:

• Secure the mount to the ceiling using the provided screws
• Ensure the bracket is level before tightening completely

3. Connect Device:

• Connect your Ethernet cable with PoE to the device
• Attach the cAP XL ac to the mount
• Pull it down until it snaps securely into place

Wall Mount Installation

1. Prepare Mounting Surface:

• Select an appropriate wall location
• Mark and drill holes for the mounting bracket
• Insert anchors if needed

2. Install Bracket and Device:

• Attach the wall mount bracket to the surface
• Connect Ethernet cable to the device
• Secure the cAP XL ac to the mount

Rack Mount Option

The cAP XL ac can also be mounted in standard 19-inch racks:

• Use the included rack mount ears
• Secure the device using rack screws
• Ensure proper cable management for PoE connections

Placement Considerations

For optimal repeater performance:

• Position the device within good range of your main router (typically 50-70% of your main router’s maximum range)
• Avoid physical obstructions between the repeater and main router
• Elevate the device when possible for better signal propagation
• Keep away from metal objects and electronic devices that may cause interference
• Ensure adequate ventilation if installing in enclosed spaces

Remember that the repeater’s location affects both its connection to your main router and its coverage area. A poorly placed repeater may not provide the expected coverage improvement or might even create connectivity issues.

Performance Considerations and Limitations

When using the MikroTik cAP XL ac in repeater mode, it’s important to understand the performance implications and limitations compared to Ethernet-connected access points.

Throughput Reduction

The most significant limitation of repeater mode is the inherent 50% throughput reduction. This occurs because:

• The device must use half its airtime receiving signals from your main router
• The remaining airtime is used for transmitting to connected devices
• This effectively halves the maximum theoretical bandwidth

In practice, you might experience:

• Speeds approximately 40-60% of your main router’s maximum throughput
• Latency increases due to the wireless hop
• Reduced performance during high-traffic periods

Range Considerations

While repeaters extend coverage, they don’t double the range. Instead:

• The repeater needs to be within good range of your main router (typically 50-70% of main router’s range)
• Devices connected to the repeater experience further range reduction
• For maximum coverage, consider multiple repeaters strategically placed

Roaming Limitations

MikroTik repeater mode doesn’t support:

• 802.11r (Fast BSS Transition)
• 802.11k (Radio Resource Measurement)
• 802.11v (BSS Transition Management)

This means:

• Devices may experience brief interruptions when moving between access points
• Seamless roaming isn’t guaranteed
• Handoffs between your main router and repeater may not be smooth

Frequency Planning

For optimal performance:

• Use different frequencies for your main router and repeater if possible
• Avoid channel overlap between networks
• Consider using 5 GHz for backhaul and 2.4 GHz for client connections (or vice versa)
• Monitor for interference from neighboring networks

When to Consider Alternatives

Repeater mode may not be ideal if:

• You need maximum performance for bandwidth-intensive applications
• You have many simultaneous connections
• Seamless roaming is critical
• Your main router is already at capacity

In these cases, consider:

• Ethernet cable connections
• Powerline adapters
• Mesh WiFi systems
• CAPsMAN for centralized management of multiple access points

Despite these limitations, the MikroTik cAP XL ac in repeater mode can still provide valuable coverage extension where running Ethernet cables is impractical or impossible.

Troubleshooting Common Issues

Even with careful setup, you may encounter issues when configuring your MikroTik cAP XL ac as a repeater. Here are some common problems and their solutions:

Connection Issues

Problem: Repeater won’t connect to main WiFi network

• Solution:
• Verify SSID and password match exactly (case-sensitive)
• Ensure the repeater is within range of the main router
• Try different frequencies or channels
• Check that security settings match (WPA2-PSK, same encryption type)

Problem: No internet access from devices connected to repeater

• Solution:
• Verify the bridge configuration between wireless interface and Eth2
• Check that DHCP is properly configured on your main router
• Ensure the repeater successfully connected to the main network

Performance Problems

Problem: Slow speeds or poor performance

• Solution:
• Move the repeater closer to the main router
• Reduce the number of connected devices
• Consider using a different frequency band
• Check for interference from other networks or devices

Problem: Intermittent connection drops

• Solution:
• Update RouterOS to the latest version
• Adjust tx-power settings to reduce interference
• Check for firmware updates for your main router
• Consider using a different WiFi channel

Configuration Errors

Problem: Can’t access the repeater’s web interface after configuration

• Solution:
• Try accessing via the default IP (192.168.88.1)
• Perform a factory reset if necessary (hold reset button for 10+ seconds)
• Check if you’re connected to the correct WiFi network
• Verify the device is powered on and LEDs indicate normal operation

Problem: Repeater connects but doesn’t broadcast its own WiFi

• Solution:
• Verify wireless interface is enabled in the correct mode
• Check SSID broadcast settings
• Ensure security settings are properly configured
• Restart the wireless interfaces

Advanced Troubleshooting

If basic troubleshooting doesn’t resolve issues:

1. Check System Logs: Navigate to “System” > “Log” for error messages
2. Monitor Interface Status: In “Interfaces”, check for error counters
3. Use WinBox for Diagnostics: Download and use WinBox for more detailed analysis
4. Test with Different Settings: Temporarily disable security features to isolate issues
5. Consult MikroTik Documentation: Refer to the official documentation for specific error codes

For persistent issues, the MikroTik community forums and Reddit can provide additional insights from other users who may have encountered similar problems with their cAP XL ac repeater setups.

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Sources

1. MikroTik cAP XL ac Official Documentation. Retrieved from https://help.mikrotik.com/docs/display/UM/cAP+XL+ac
2. Quick Guide - cAP XL ac. Retrieved from https://help.mikrotik.com/docs/spaces/QG/pages/63406151/Quick+Guide+-+cAP+XL+ac
3. Configuring repeater - RouterOS. Retrieved from https://help.mikrotik.com/docs/spaces/ROS/pages/313262189/Configuring+repeater
4. cAP ac - User manuals. Retrieved from https://help.mikrotik.com/docs/spaces/UM/pages/16351551/cAP+ac
5. MikroTik cAP XL ac Product Page. Retrieved from https://mikrotik.com/product/cap_xl_ac
6. cAP XL ac Mounting Instructions. Retrieved from https://cdn.mikrotik.com/web-assets/product_files/cAPXLacmountinginstruction_210923.pdf
7. r/mikrotik Community Discussion. Retrieved from https://www.reddit.com/r/mikrotik/comments/ttekej/issues_with_mikrotik_cap_as_repeater_with/

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Conclusion

Setting up your MikroTik cAP XL ac as a wireless repeater without Ethernet cable provides a practical solution for extending WiFi coverage where running cables isn’t feasible. The configuration process involves powering the device via PoE, connecting to its temporary WiFi network, accessing the web interface, and configuring the wireless settings in repeater mode. While this setup offers convenience, it’s important to understand the performance limitations, particularly the 50% throughput reduction and lack of advanced roaming support.

By following the step-by-step process outlined in this guide, considering proper placement for optimal signal strength, and being aware of the inherent limitations of repeater mode, you can successfully deploy your MikroTik cAP XL ac to enhance your wireless network coverage. For applications requiring maximum performance or seamless roaming, consider alternative solutions like Ethernet connections or mesh WiFi systems, but for basic coverage extension, the repeater configuration on the cAP XL ac provides an effective solution.