FRP Accept New Mux Stream Error Keepalive Timeout Fix Guide

If you’re seeing the “frp accept new mux stream error keepalive timeout” message, it means the FRP client and server have lost their connection due to silence or inactivity. This issue is common and fixable. In this article, you’ll learn the reasons for the error, how to fix it, and what settings to check.

We’ll also cover related FRP connection issues to help you fix them all in one go.

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FRP Keepalive Timeout Solution for Beginners

Keepalive settings tell FRP how long to wait before checking if the other side is still online.

To solve timeout issues:

• Open both frpc.ini and frps.ini files
  
• Add this line if it doesn’t exist:
  heartbeat_timeout = 90
  
• This increases the waiting time before disconnecting
  
• Save and restart both client and server
  

This fix works best on weak or slow networks.

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FRP Mux Stream Error Fix

Mux stream means combining several connections into one. If too many streams pile up or the connection is weak, this can fail.

To fix:

• Add to both .ini files:
  disable_multiplexing = true
  
• Restart FRP to apply the change
  

Disabling multiplexing stops FRP from overloading the stream.

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FRP Connection Timeout Troubleshooting Tips

Here’s what to check if you’re facing connection timeout issues:

• Make sure both devices have a stable internet connection
  
• Confirm that firewall rules are not closing idle ports
  
• Avoid using restricted networks like public Wi-Fi
  
• Update to the latest version of FRP
  

Turn on debug logging for more details:

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FRP Accept New Mux Stream Error (Reason)

The root causes of this error often include:

• Bad or slow network connections
  
• Incorrect keepalive timeout values
  
• Internet Service Provider (ISP) interference
  
• Too many streams handled at once
  

You can read the official FRP documentation for configuration help.

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FRP Broken Pipe Error

This error means the connection was closed while data was being sent.

Fixes:

• Restart both the server and client
  
• Keep the client running using tools like nohup or a shell loop
  
• Increase timeout settings to avoid sudden disconnects
  

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FRP Client Disconnect Issue

The FRP client may disconnect due to:

• Poor mobile networks
  
• Weak Wi-Fi signals
  
• Battery-saving modes close the app
  

You can stop the client from quitting on failure:

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FRP Network Exception Error

This happens when the network becomes unstable.

Steps to fix:

• Sync your system clock using NTP (Network Time Protocol)
  
• Set correct DNS in your system
  
• Use a wired connection if possible
  

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FRP TLS Keepalive Error

This happens when using TLS (encrypted connections). FRP may think the connection has failed if it gets no response.

Try this:

• Temporarily turn off TLS:
  tls_enable = false
  

If the error goes away, the problem is TLS-related. You can troubleshoot your TLS settings from there.

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FRP Server Keepalive Settings

To reduce disconnects from the server side, use this config:

Longer timeout settings give your devices more time to reconnect.

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FRP Proxy Connection Lost

If you see a proxy connection lost, try the following:

• Restart your proxy service on the server
  
• Check internet stability
  
• Add a watchdog or cron job to restart the client regularly
  

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FRP Stream Error Log Analysis

Enable log files to understand stream errors:

Review log messages to see where and when the error starts.

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FRP Work Connection Timeout

This error may show up if your network drops idle or long connections. One user fixed this by:

• Using a mobile hotspot overnight
  
• Restarting FRP hourly using a scheduled task
  

This kept the connection alive even when the main network failed.

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FRP TLS Client Certificate Error

TLS client cert errors happen when FRP can’t find or use a certificate.

Make sure you have:

And that both files are valid and readable.

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FRP Server Client Connection Drops

If your FRP client drops randomly, check:

• Battery-saving settings (disable app sleeping)
  
• Network type (use stable broadband, not mobile)
  
• System suspend mode (avoid system sleep)
  

Run the client in the background using tmux or screen.

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FRP Debug Keepalive Timeout

To fully debug a keepalive timeout:

• Enable debug logs
  
• Use Wireshark or tcpdump to capture traffic
  
• Compare timestamps for dropped packets
  

You’ll know exactly when and why the connection dropped.

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FRP Transport TLS Force Setting

To make TLS required for all connections:

This encrypts everything from start to end, helping on public or untrusted networks.

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FRP Mux Stream Broken Pipe

A broken pipe means the data flow was cut unexpectedly.

Fix it by:

• Turning off muxing
  
• Reducing the number of active streams
  
• Ensuring enough bandwidth
  

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FRP Client Auto Disconnect

You can keep the client running with this loop script:

This auto-restarts the client if it crashes or disconnects.

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FRP Proxy Closing Error

This error happens when:

• The proxy crashes or is stopped
  
• The TLS handshake breaks
  
• A stale session gets reused
  

Fix by:

• Restarting both the client and server
  
• Clearing old sessions
  

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FRP EOF Mux Stream Error

EOF means “End of File,” or one side shuts the connection.

Fix tips:

• Ensure the server isn’t restarting often
  
• Check that your script doesn’t stop unexpectedly
  
• Use TLS with proper settings
  

You can also learn more about reverse proxy reliability in this Cloudflare blog post.

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Conclusion

You now have a complete guide to fix the “frp accept new mux stream error keepalive timeout” and other common FRP issues.

Here’s a quick summary:

• Increase heartbeat_timeout to avoid timeout errors
  
• Disable multiplexing to fix stream issues
  
• Use reconnect scripts to stay online
  
• Always check network and TLS settings
  
• Use debug logging to trace problems fast
  

Stay updated with the latest FRP version, and you’ll avoid most of these errors altogether.