https://github.com/luizbizzio/tailscale-mtu
🌐 Scripts to configure persistent MTU settings for Tailscale on Linux and Windows, enhancing network performance with automated and customizable setups.
https://github.com/luizbizzio/tailscale-mtu
automation bash cross-platform devops iot linux mtu network-optimization network-performance network-tools networking open-source powershell scripts shell-scripts tailscale udev-rules vpn windows wireguard
Last synced: about 2 months ago
JSON representation
🌐 Scripts to configure persistent MTU settings for Tailscale on Linux and Windows, enhancing network performance with automated and customizable setups.
- Host: GitHub
- URL: https://github.com/luizbizzio/tailscale-mtu
- Owner: luizbizzio
- License: mit
- Created: 2025-01-04T11:36:15.000Z (5 months ago)
- Default Branch: main
- Last Pushed: 2025-04-12T16:34:49.000Z (about 2 months ago)
- Last Synced: 2025-04-15T16:00:07.012Z (about 2 months ago)
- Topics: automation, bash, cross-platform, devops, iot, linux, mtu, network-optimization, network-performance, network-tools, networking, open-source, powershell, scripts, shell-scripts, tailscale, udev-rules, vpn, windows, wireguard
- Language: PowerShell
- Homepage:
- Size: 134 KB
- Stars: 15
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# Tailscale MTU Configuration ⚙️
This repository provides step-by-step instructions and scripts to make the MTU configuration for Tailscale persistent on both Linux and Windows. Each section is tailored to its operating system and includes explanations for every step.
---
## Important Considerations ⚠️
- **Devices with Fixed MTU**:
- If you have devices in your Tailscale network that **do not allow MTU adjustments** (e.g., smartphones, IoT devices), increasing the MTU on other devices may cause **packet fragmentation**. This can lead to performance issues, including slower speeds or connectivity problems.
- It is **not recommended** to use a larger MTU unless all devices in your Tailscale network support it.
- **Determine the Correct MTU**:
- The ideal MTU value varies depending on your network configuration. It is crucial to determine the correct MTU for your network through careful testing.
- For example, in some configurations, a value of **1400** works well for **direct connections** between devices in the Tailscale network. However, for **DERP (relayed) connections**, using a higher MTU may lead to **packet loss** and significantly degrade network performance.
---
## Why Adjust the MTU? 🤔
Tailscale defaults to an MTU of 1280 for compatibility with most networks, but in some situations, increasing the MTU to 1500 can improve network performance. This is particularly useful in environments where fragmentation is not a concern.
## Table of Contents 📋
- [Linux Configuration 🐧](#linux-configuration-)
- [Windows Configuration 🪟](#windows-configuration-)
- [License 📜](#license-)
## Linux Configuration 🐧
### **Option 1: Automatic Setup** (Recommended) ✅
1. **Run the script directly from the URL:**
- Open a terminal and run the following command as `root`:
```bash
curl -fsSL https://raw.githubusercontent.com/luizbizzio/tailscale-mtu/refs/heads/main/linux-setup.sh | sudo bash
```
2. **What This Does:**
- The script performs the following actions:
- Creates a `udev` rule to ensure the Tailscale interface (`tailscale0`) always has an MTU of **1500**.
- Reloads the `udev` rules and applies them.
- Verifies that the MTU is correctly set.
- This setup ensures the configuration is persistent, even after system reboots or network resets.
---
### **Option 2: Manual Setup**
1. **Create a `udev` rule:**
- Open a terminal and run the following command to create a new rule file:
```bash
sudo nano /etc/udev/rules.d/99-tailscale-mtu.rules
```
2. **Add the rule to the file:**
- Paste the following content into the file:
```bash
ACTION=="add", SUBSYSTEM=="net", KERNEL=="tailscale0", RUN+="/sbin/ip link set dev tailscale0 mtu 1500"
```
3. **Reload the rules and apply them:**
- Run the following commands to activate the new rule:
```bash
sudo udevadm control --reload-rules
sudo udevadm trigger --subsystem-match=net --action=add
```
4. **Check the MTU size**
- Verify if the MTU for the `tailscale0` interface has been set to `1500`:
```bash
ip link show tailscale0
```
### Explanation 📝
Here’s what the bash script does step by step:
- **`ACTION=="add"`**: The rule triggers when a network device is added.
- **`SUBSYSTEM=="net"`**: Applies only to network devices.
- **`KERNEL=="tailscale0"`**: Targets the Tailscale interface.
- **`RUN+="/sbin/ip link set dev tailscale0 mtu 1500"`**: Ensures the MTU is set to 1500 whenever the Tailscale interface is initialized.
---
## Windows Configuration 🪟
### **Option 1: Automatic Setup** (Recommended) ✅
1. **Run the script directly from the URL:**
- Open a PowerShell terminal as Administrator.
- Run the following command:
```powershell
Set-ExecutionPolicy -Scope Process -ExecutionPolicy Bypass -Force; Invoke-Expression ((New-Object System.Net.WebClient).DownloadString('https://raw.githubusercontent.com/luizbizzio/tailscale-mtu/refs/heads/main/windows-setup.ps1'))
```
2. **What This Does:**
- This script ensures that the Tailscale interface will always have an MTU of **1500**, even after a system reboot or network reset.
- It achieves this by creating a scheduled task that runs in the background. The task periodically checks the Tailscale interface and adjusts the MTU to 1500 if necessary, ensuring the configuration persists.
3. **Verify MTU Configuration:**
- After running the command, the MTU size of the Tailscale interface will be displayed. You can confirm that it's set to **1500**.
---
### **Option 2: Manual Setup**
1. **Download the PowerShell script:**
- Save the [windows-setup.ps1](https://raw.githubusercontent.com/luizbizzio/tailscale-mtu/refs/heads/main/windows-setup.ps1) file to your computer.
2. **Run the script as Administrator:**
- Open a PowerShell terminal as Administrator.
- Navigate to the directory where the script is saved.
- Execute the script:
```powershell
Set-ExecutionPolicy -Scope Process -ExecutionPolicy Bypass; ./windows-setup.ps1
```
3. **Verify the MTU configuration:**
- The script automatically displays the current MTU value for the Tailscale interface after execution.
- If you wish to check the MTU again later, you can run the following command:
```powershell
netsh interface ipv4 show interfaces
```
- Locate the Tailscale interface in the output and confirm that the MTU column displays **1500**.
---
### Explanation 📝
Here’s what the PowerShell script does step by step:
- The first part of the command, `Set-ExecutionPolicy -Scope Process -ExecutionPolicy Bypass`, temporarily allows unsigned scripts to run in the current session without changing the system's global execution policy.
- **`$taskName`**: Names the task as `Tailscale-MTU`.
- **`$scriptCommand`**: Continuously monitors the `Tailscale` interface and adjusts the MTU if needed.
- **Scheduled Task Settings**:
- `RunLevel Highest`: Ensures administrative privileges.
- `WindowStyle Hidden`: Runs the script silently in the background.
---
### Note 📜
You can modify the MTU value to suit your needs. Replace `1500` in the commands or scripts with the desired MTU value.
For Linux, modify the `RUN+="/sbin/ip link set dev tailscale0 mtu 1500"` line in the `udev` rule file to set your preferred MTU value.
For Windows, update the `1500` in the PowerShell script on `$scriptCommand` part to the MTU value you want.
---
## License 📄
This repository is licensed under the [MIT License](./LICENSE).