docs: add agent bootstrap and contract read router

This commit is contained in:
Mikhail Chusavitin
2026-04-02 13:48:36 +03:00
parent 688b87e98d
commit 1d89a4918e
22 changed files with 883 additions and 1284 deletions

View File

@@ -0,0 +1,90 @@
# Alpine LiveCD Pattern Notes
This file keeps examples and rationale. The normative rules live in `contract.md`.
## Minimal mkimage Profile
```sh
profile_<name>() {
arch="x86_64"
hostname="<hostname>"
apkovl="genapkovl-<name>.sh"
image_ext="iso"
output_format="iso"
kernel_flavors="lts"
initfs_cmdline="modules=loop,squashfs,sd-mod,usb-storage quiet"
initfs_features="ata base cdrom ext4 mmc nvme raid scsi squashfs usb virtio"
grub_mod="all_video disk part_gpt part_msdos linux normal configfile search search_label efi_gop fat iso9660 cat echo ls test true help gzio"
apks="alpine-base linux-lts linux-firmware-none ..."
}
```
`arch` is the easiest field to miss. Without it, mkimage may silently skip the profile.
## apkovl Placement
`genapkovl-<name>.sh` must be in the current working directory when mkimage runs.
Example:
```sh
cp "genapkovl-<name>.sh" ~/.mkimage/
cp "genapkovl-<name>.sh" /var/tmp/
cd /var/tmp
sh mkimage.sh --workdir /var/tmp/work ...
```
## `/var/tmp` Build Root
Use `/var/tmp` instead of `/tmp`:
```sh
export TMPDIR=/var/tmp
cd /var/tmp
sh mkimage.sh ...
```
On Alpine builders, `/tmp` is often a small tmpfs and firmware/modloop builds overflow it.
## Cache Reuse
Typical cache-preserving cleanup:
```sh
if [ -d /var/tmp/bee-iso-work ]; then
find /var/tmp/bee-iso-work -maxdepth 1 -mindepth 1 \
-not -name 'apks_*' \
-not -name 'kernel_*' \
-not -name 'syslinux_*' \
-not -name 'grub_*' \
-exec rm -rf {} +
fi
```
The apkovl section should still be rebuilt every time.
## Faster Squashfs
```sh
mkdir -p /etc/mkinitfs
grep -q 'MKSQUASHFS_OPTS' /etc/mkinitfs/mkinitfs.conf 2>/dev/null || \
echo 'MKSQUASHFS_OPTS="-comp lz4 -Xhc"' >> /etc/mkinitfs/mkinitfs.conf
```
## Long-Running Builds
```sh
apk add screen
screen -dmS build sh -c "sh build.sh > /var/log/build.log 2>&1"
tail -f /var/log/build.log
```
## Firmware Reminder
Typical extra firmware packages:
- `linux-firmware-intel`
- `linux-firmware-mellanox`
- `linux-firmware-bnx2x`
- `linux-firmware-rtl_nic`
- `linux-firmware-other`

View File

@@ -7,136 +7,17 @@ Version: 1.0
Rules for building bootable Alpine Linux ISO images with custom overlays using `mkimage.sh`.
Applies to any project that needs a LiveCD: hardware audit, rescue environments, kiosks.
---
See `README.md` for detailed examples and build snippets.
## mkimage Profile
## Rules
Every project must have a profile file `mkimg.<name>.sh` defining:
```sh
profile_<name>() {
arch="x86_64" # REQUIRED — without this mkimage silently skips the profile
hostname="<hostname>"
apkovl="genapkovl-<name>.sh"
image_ext="iso"
output_format="iso"
kernel_flavors="lts"
initfs_cmdline="modules=loop,squashfs,sd-mod,usb-storage quiet"
initfs_features="ata base cdrom ext4 mmc nvme raid scsi squashfs usb virtio"
grub_mod="all_video disk part_gpt part_msdos linux normal configfile search search_label efi_gop fat iso9660 cat echo ls test true help gzio"
apks="alpine-base linux-lts linux-firmware-none ..."
}
```
**`arch` is mandatory.** If missing, mkimage silently builds nothing and exits 0.
---
## apkovl Mechanism
The apkovl is a `.tar.gz` overlay extracted by initramfs at boot, overlaying `/etc`, `/usr`, `/root`.
`genapkovl-<name>.sh` generates the tarball:
- Must be in the **CWD** when mkimage runs — not only in `~/.mkimage/`
- `~/.mkimage/` is searched for mkimg profiles only, not genapkovl scripts
```sh
# Copy both scripts to ~/.mkimage AND to CWD (typically /var/tmp)
cp "genapkovl-<name>.sh" ~/.mkimage/
cp "genapkovl-<name>.sh" /var/tmp/
cd /var/tmp
sh mkimage.sh --workdir /var/tmp/work ...
```
---
## Build Environment
**Always use `/var/tmp`, not `/tmp`:**
```sh
export TMPDIR=/var/tmp
cd /var/tmp
sh mkimage.sh ...
```
`/tmp` on Alpine builder VMs is typically a 1GB tmpfs. Kernel firmware squashfs alone exceeds this.
`/var/tmp` uses actual disk space.
---
## Workdir Caching
mkimage stores each ISO section in a hash-named subdirectory. Preserve expensive sections across builds:
```sh
# Delete everything EXCEPT cached sections
if [ -d /var/tmp/bee-iso-work ]; then
find /var/tmp/bee-iso-work -maxdepth 1 -mindepth 1 \
-not -name 'apks_*' \ # downloaded packages
-not -name 'kernel_*' \ # modloop squashfs
-not -name 'syslinux_*' \ # syslinux bootloader
-not -name 'grub_*' \ # grub EFI
-exec rm -rf {} +
fi
```
The apkovl section is always regenerated (contains project-specific config that changes per build).
---
## Squashfs Compression
Default compression is `xz` — slow but small. For RAM-loaded modloops, size rarely matters.
Use `lz4` for faster builds:
```sh
mkdir -p /etc/mkinitfs
grep -q 'MKSQUASHFS_OPTS' /etc/mkinitfs/mkinitfs.conf 2>/dev/null || \
echo 'MKSQUASHFS_OPTS="-comp lz4 -Xhc"' >> /etc/mkinitfs/mkinitfs.conf
```
Apply before running mkimage. Rebuilds modloop only when kernel version changes.
---
## Long Builds
NVIDIA driver downloads, kernel compiles, and package fetches can take 1030 minutes.
Run in a `screen` session so builds survive SSH disconnects:
```sh
apk add screen
screen -dmS build sh -c "sh build.sh > /var/log/build.log 2>&1"
tail -f /var/log/build.log
```
---
## NIC Firmware
`linux-firmware-none` (default) contains zero firmware files. Real hardware NICs often require firmware.
Include firmware packages matching expected hardware:
```
linux-firmware-intel # Intel NICs (X710, E810, etc.)
linux-firmware-mellanox # Mellanox/NVIDIA ConnectX
linux-firmware-bnx2x # Broadcom NetXtreme
linux-firmware-rtl_nic # Realtek
linux-firmware-other # catch-all
```
---
## Versioning
Pin all versions in a single `VERSIONS` file sourced by all build scripts:
```sh
ALPINE_VERSION=3.21
KERNEL_VERSION=6.12
GO_VERSION=1.23.6
NVIDIA_DRIVER_VERSION=590.48.01
```
Never hardcode versions inside build scripts.
- Every project must have `mkimg.<name>.sh`.
- `arch` is mandatory in the mkimage profile. If it is missing, `mkimage.sh` may exit 0 without building anything.
- The `apkovl` generator `genapkovl-<name>.sh` must be present in the current working directory when `mkimage.sh` runs.
- `~/.mkimage/` is for mkimg profiles only. Do not assume mkimage will find `genapkovl` there.
- Run builds in `/var/tmp`, not `/tmp`. LiveCD builds often exceed typical `/tmp` tmpfs size.
- Preserve expensive mkimage cache sections between builds when possible. Regenerate the apkovl section every build.
- For RAM-loaded modloops, prefer faster squashfs settings such as `lz4` unless the project explicitly optimizes for smallest ISO size.
- Long builds must run in a resilient session (`screen`, `tmux`, or equivalent) so SSH disconnects do not kill the build.
- `linux-firmware-none` alone is not sufficient for real hardware targets. Include firmware packages matching the expected NIC/storage hardware.
- Pin all build-critical versions in one shared versions file sourced by the build scripts. Do not hardcode versions inline in multiple scripts.