cmd/lopower: flesh out README

Change-Id: Iece542369f4124a3e7e46653211b081bce601a29
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
This commit is contained in:
Brad Fitzpatrick 2024-11-04 07:56:09 -08:00 committed by Anton Tolchanov
parent c142623d69
commit 404dd02624
2 changed files with 14 additions and 0 deletions

View File

@ -10,6 +10,10 @@ Some small devices such as ESP32 microcontrollers [support WireGuard](https://gi
Tailscale LOPOWER is a proxy that you run nearby that bridges a low-power WireGuard-speaking device on one side to Tailscale on the other side. That way network traffic from the low-powered device never hits the network unencrypted but is still able to communicate to/from other Tailscale devices on your Tailnet.
## Diagram
<img src="./lopower.svg">
## Features
* Runs separate Wireguard server with separate keys (unknown to the Tailscale control plane) that proxy on to Tailscale
@ -24,3 +28,12 @@ Tailscale LOPOWER is a proxy that you run nearby that bridges a low-power WireGu
* this runs in userspace using gVisor's netstack. That means it's portable (and doesn't require kernel/system configuration), but that does mean it doesn't operate at a packet level but rather it stitches together two separate TCP (or UDP) flows and doesn't support IP protocols such as SCTP or other things that aren't TCP or UDP.
* the standard WireGuard configuration doesn't support specifying DNS search domains, so resolving bare names like the `go` in `http://go/foo` won't work and you need to resolve names using the fully qualified `go.your-tailnet.ts.net` names.
* since it's based on userspace tsnet mode, it doesn't pick up your system DNS configuration (yet?) and instead resolves non-tailnet DNS names using either your "Override DNS" tailnet settings for the global DNS resolver, or else defaults to `8.8.8.8` and `1.1.1.1` (using DoH) if that isn't set.
## TODO
* provisioning more than one low-powered device is possible, but requires manual config file edits. It should be possible to enroll multuple devices (including QR code support) easily.
* incoming connections (from Tailscale to `lopower`) don't yet forward to the low-powered devices. When there's only one low-powered device, the mapping policy is obvious. When there are multiple, it's not as obvious. Maybe the answer is supporting [4via6 subnet routers](https://tailscale.com/kb/1201/4via6-subnets).
## Installing
* git clone this repo, switch to `lp` branch, `go install ./cmd/lopower` and see `lopower --help`.

1
cmd/lopower/lopower.svg Normal file

File diff suppressed because one or more lines are too long

After

Width:  |  Height:  |  Size: 114 KiB