Add new article for macos vpn

Signed-off-by: Zhenbo Li <[email protected]>

Author: Endle

_posts/2025-03-15-macos-sequoia-1531-share-vpn-to-windows-laptop.md

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+---
+layout: post
+title: "macOS Sequoia 15.3.1 Share VPN to Windows Laptop"
+description: ""
+category: 
+tags: []
+---
+
+#### TL;DR 
+[L2TP](https://en.wikipedia.org/wiki/Layer_2_Tunneling_Protocol) is a must. WireGuard and IKEv2 are not supported.
+
+#### Background 
+I have a personal MacBook running macOS Sequoia 15.3.1, and a Windows 11 laptop managed by my school. While using a public Wi-Fi, I want my MacBook to share the VPN to the Windows laptop.
+
+When MacBook is connected to Wi-Fi, [it can only share Internet with Ethernet](https://apple.stackexchange.com/questions/25878/how-can-i-create-an-ad-hoc-connection-from-my-macbook-pro-wifi-connection)
+
+
+#### Physical Set-up 
+A USB-C hub adapter needs to be connected to macbook to provide an ethernet port. My Windows laptop doesn't have an ethernet port,so we need the second USB hub adapter.
+
+#### macOS Set-up 
+
+Settings -> VPN -> Add VPN Configuration -> L2TP over IPSec  
+![Add VPN](/images/2025/macos_vpn/add_l2tp.png)
+
+L2TP -> Options -> Send all traffic over VPN connection
+
+
+![Send traffic](/images/2025/macos_vpn/send_all.png)
+
+
+When the L2TP VPN is added and enabled, we can share the Internet now.  
+
+Settings -> General -> Internet Sharing -> More
+
+![Internet Sharing](/images/2025/macos_vpn/sharing.png)
+
+In the config dialog, set *Share your connection from* to *Wi-FI*, and enable AX88179A.
+
+
+![Internet Sharing Device](/images/2025/macos_vpn/share_more.png)
+
+Enjoy!
+
+#### Epilogue 
+
+When MacBook is connected to Wi-Fi, [it can also share Internet with Thunderbolt](https://support.apple.com/en-ca/guide/mac-help/mchld53dd2f5/mac). Sadly, my Windows laptop doesn't have one.  
+
+iPhone's USB tethering is limited. Only the cellular connection can be shared. [link](https://support.apple.com/en-ca/guide/iphone/iph45447ca6/ios)
+
+Vanilla Android doesn't route VPN traffic when tethering [link](https://protonvpn.com/support/share-vpn-connection-android-hotspot). Modified Android like AOSP may have an option **Allow clients to use VPNs** [link1](https://www.reddit.com/r/VPN/comments/m13d0h/comment/gqbdist/) [link2](https://github.com/PixelExperience/android-issues/issues/5932). After rooting, there are several apps doing so, including [VPNHotspot](https://github.com/Mygod/VPNHotspot). Sadly (again), my Samsung Tablet at hand [can't unlock bootloader](https://www.reddit.com/r/androidroot/comments/1g2xhd9/unlock_bootloader_for_newer_samsung_devices_in/).

images/2025/macos_vpn/add_l2tp.png

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+{ pkgs ? import <nixpkgs> {} }:
+  pkgs.mkShell {
+    nativeBuildInputs = with pkgs.buildPackages; [
+      rubyPackages_3_2.jekyll
+      rubyPackages_3_2.rake
+      rubyPackages_3_2.jekyll-paginate
+      rubyPackages_3_2.kramdown-parser-gfm
+      rubyPackages_3_2.webrick
+      ruby_3_2
+    ];
+}
+