Brad FitzpatrickandBrad Fitzpatrick
76eece2d15
Several improvements to the gokrazy appliance build and flash workflow:
gokrazy/build.go:
- Round Pi image size up to a power of 2 (QEMU raspi3b requires it)
- Use monogok's mkfs.Perm for the /perm ext4 partition (pure Go,
cross-platform, no e2fsprogs dependency)
gokrazy/mkfs:
- Accept optional PermFile entries to include in the freshly-created
ext4 filesystem (used for breakglass authorized_keys)
- Use progresstracking.Ticker for flush progress reporting
gokrazy/tsapp*/config.json:
- Point breakglass at /perm/breakglass.authorized_keys (not ec2)
- Fix Pi SerialConsole to serial0,115200 (not ttyS0)
cmd/tailscale/cli/configure-flash-appliance.go:
- Add --add-ssh-authorized-keys flag to write an authorized_keys
file into /perm during flash (for breakglass SSH access)
- Use progresstracking.CountingWriter + Ticker for write progress
Makefile:
- tsapp-build-and-flash-pi: auto-include ~/.ssh/id_ed25519.pub
- tsapp-qemu-pi: use virt machine + UEFI + ramfb + e1000 (working
network + framebuffer), with DTB watchdog patch and
gokrazy.log_to_serial for debugging
- Auto-detect UEFI firmware path across Debian/Homebrew/Fedora
Updates #1866
Change-Id: Ifa97ad34c509a81e1637d9bce12a788037dfe5ec
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Tailscale Appliance Gokrazy Image
This is (as of 2024-06-02) a WORK IN PROGRESS (pre-alpha) experiment to package Tailscale as a Gokrazy appliance image for use on both VMs (AWS, GCP, Azure, Proxmox, ...) and Rasperry Pis.
See https://github.com/tailscale/tailscale/issues/1866
Overview
It makes a ~70MB image (about the same size as
tailscale-setup-full-1.66.4.exe and smaller than the combined
Tailscale Android APK) that combines the Linux kernel and Tailscale
and that's it. Nothing written in C. (except optional busybox for
debugging) So no operating system to maintain. Gokrazy has three
partitions: two read-only ones (one active at a time, the other for
updates for the next boot) and one optional stateful, writable
partition that survives upgrades (/perm/)
Initial bootstrap configuration of this appliance will be over either serial or configuration files (auth keys, subnet routes, etc) baked into the image (for Raspberry Pis) or in cloud-init/user-data (for AWS, etc). As of 2024-06-02, AWS user-data config files work.
Quick start
Install dependencies:
$ brew install qemu e2fsprogs
Build + launch:
$ make qemu
That puts serial on stdio. To exit the serial console and escape to
the qemu monitor, type Ctrl-a c. Then type quit in the monitor to
quit.
Building
make image to build just the image (tsapp.img), without uploading it.
UTM
You can also use UTM, but the qemu path above is easier. For UTM, see the UTM instructions.
AWS
Build an AMI
go run build.go --bucket=your-S3-temp-bucket to build an AMI. Make
sure your "aws" command is in your path and has access.
Creating an instance
When creating an instance, you need a Nitro machine type to get a
virtual serial console. Notably, that means the t2.* instance types
that AWS pushes as a free option are not new enough. Use t3.* at least.
As of 2024-06-02 this builder tool only supports x86_64 (arm64 should be trivial and will come soon), so don't use a Graviton machine type.
To connect to the serial console, you can either use the web console, or use the CLI like:
$ aws ec2-instance-connect send-serial-console-ssh-public-key --instance-id i-0b4a0eabc43629f13 --serial-port 0 --ssh-public-key file:///your/home/.ssh/id_ed25519.pub --region us-west-2
{
"RequestId": "a93b0ea3-9ff9-45d5-b8ed-b1e70ccc0410",
"Success": true
}
$ ssh i-0b4a0eabc43629f13.port0@serial-console.ec2-instance-connect.us-west-2.aws