From 5f3d60ef0f818e4b5e0b89ca4b18f492ffb14380 Mon Sep 17 00:00:00 2001 From: Thales Maciel Date: Sun, 1 Feb 2026 15:37:24 -0300 Subject: [PATCH] Fix restore config parsing --- restore.sh | 244 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 244 insertions(+) create mode 100755 restore.sh diff --git a/restore.sh b/restore.sh new file mode 100755 index 0000000..60af354 --- /dev/null +++ b/restore.sh @@ -0,0 +1,244 @@ +#!/usr/bin/env bash +set -euo pipefail + +log() { + printf '[restore] %s\n' "$*" +} + +usage() { + cat <<'EOF' +Usage: ./restore.sh + +Restarts a VM using existing disks and COW snapshot. +EOF +} + +find_vm_meta() { + local query="$1" + local meta_json match_count=0 match="" + + for meta_json in state/vms/*/meta.json; do + [[ -f "$meta_json" ]] || continue + local id name + id="$(jq -r '.id // empty' "$meta_json")" + name="$(jq -r '.name // empty' "$meta_json")" + if [[ "$id" == "$query"* || "$name" == "$query"* ]]; then + match="$meta_json" + match_count=$((match_count + 1)) + fi + done + + if (( match_count == 0 )); then + log "no VM found for prefix: $query" + exit 1 + fi + if (( match_count > 1 )); then + log "multiple VMs found for prefix: $query" + exit 1 + fi + + printf '%s' "$match" +} + +QUERY="${1:-}" +if [[ -z "$QUERY" || "$QUERY" == "-h" || "$QUERY" == "--help" ]]; then + usage + exit 1 +fi + +DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)" +FC_BIN="$DIR/firecracker" + +if ! command -v jq >/dev/null 2>&1; then + log "jq is required" + exit 1 +fi +if ! command -v dmsetup >/dev/null 2>&1 || ! command -v losetup >/dev/null 2>&1 || ! command -v blockdev >/dev/null 2>&1; then + log "dmsetup, losetup, and blockdev are required" + exit 1 +fi +if ! command -v e2cp >/dev/null 2>&1 || ! command -v e2rm >/dev/null 2>&1; then + log "e2cp and e2rm are required" + exit 1 +fi + +META_JSON="$(find_vm_meta "$QUERY")" +VM_DIR="$(dirname "$META_JSON")" +VM_JSON="$VM_DIR/vm.json" + +ROOTFS="$(jq -r '.rootfs // empty' "$META_JSON")" +KERNEL="$(jq -r '.kernel // empty' "$META_JSON")" +HOME_PATH="$(jq -r '.home_path // empty' "$META_JSON")" +VAR_PATH="$(jq -r '.var_path // empty' "$META_JSON")" +TAP_DEV="$(jq -r '.tap // empty' "$META_JSON")" +API_SOCK="$(jq -r '.api_sock // empty' "$META_JSON")" +LOG_FILE="$(jq -r '.log // empty' "$META_JSON")" +GUEST_IP="$(jq -r '.guest_ip // empty' "$META_JSON")" +DM_NAME="$(jq -r '.dm_name // empty' "$META_JSON")" +COW_FILE="$(jq -r '.cow_file // empty' "$META_JSON")" + +if [[ -z "$ROOTFS" || -z "$KERNEL" || -z "$HOME_PATH" || -z "$VAR_PATH" || -z "$API_SOCK" || -z "$TAP_DEV" || -z "$GUEST_IP" || -z "$DM_NAME" || -z "$COW_FILE" ]]; then + log "meta.json missing required fields" + exit 1 +fi +if [[ ! -f "$ROOTFS" || ! -f "$KERNEL" || ! -f "$HOME_PATH" || ! -f "$VAR_PATH" || ! -f "$COW_FILE" || ! -f "$FC_BIN" ]]; then + log "missing disk/kernel file(s)" + exit 1 +fi +if [[ ! -f "$VM_JSON" ]]; then + log "vm.json missing: $VM_JSON" + exit 1 +fi + +sudo -v + +BR_DEV="br-fc" +BR_IP="172.16.0.1" +CIDR="24" +DNS_SERVER="1.1.1.1" + +VM_STARTED=0 +cleanup() { + if [[ "$VM_STARTED" -eq 1 ]]; then + return + fi + sudo ip link del "$TAP_DEV" 2>/dev/null || true + rm -f "$API_SOCK" +} +trap cleanup EXIT + +# Host bridge +if ! ip link show "$BR_DEV" >/dev/null 2>&1; then + log "creating host bridge $BR_DEV ($BR_IP/$CIDR)" + sudo ip link add name "$BR_DEV" type bridge + sudo ip addr add "${BR_IP}/${CIDR}" dev "$BR_DEV" + sudo ip link set "$BR_DEV" up +else + sudo ip link set "$BR_DEV" up +fi + +sock_dir="$(dirname "$API_SOCK")" +sudo mkdir -p "$sock_dir" +sudo chown "$(id -u):$(id -g)" "$sock_dir" + +# Recreate dm-snapshot +sudo dmsetup remove "$DM_NAME" 2>/dev/null || true +BASE_LOOP="$(sudo losetup -f --show --read-only "$ROOTFS")" +COW_LOOP="$(sudo losetup -f --show "$COW_FILE")" +SECTORS="$(sudo blockdev --getsz "$BASE_LOOP")" +sudo dmsetup create "$DM_NAME" --table "0 $SECTORS snapshot $BASE_LOOP $COW_LOOP P 8" +DM_DEV="/dev/mapper/$DM_NAME" + +jq \ + --arg base_loop "$BASE_LOOP" \ + --arg cow_loop "$COW_LOOP" \ + --arg dm_dev "$DM_DEV" \ + '.base_loop=$base_loop | .cow_loop=$cow_loop | .dm_dev=$dm_dev' \ + "$META_JSON" > "$META_JSON.tmp" && mv "$META_JSON.tmp" "$META_JSON" + +# Update /etc/resolv.conf and hostname in snapshot +RESOLV_TMP="$VM_DIR/resolv.conf" +HOSTNAME_TMP="$VM_DIR/hostname" +HOSTS_TMP="$VM_DIR/hosts" +printf 'nameserver %s\n' "$DNS_SERVER" >"$RESOLV_TMP" +printf '%s\n' "$(jq -r '.name // empty' "$META_JSON")" >"$HOSTNAME_TMP" +printf '127.0.0.1 localhost\n127.0.1.1 %s\n' "$(jq -r '.name // empty' "$META_JSON")" >"$HOSTS_TMP" +sudo e2rm "$DM_DEV:/etc/resolv.conf" >/dev/null 2>&1 || true +sudo e2rm "$DM_DEV:/etc/hostname" >/dev/null 2>&1 || true +sudo e2rm "$DM_DEV:/etc/hosts" >/dev/null 2>&1 || true +sudo e2cp "$RESOLV_TMP" "$DM_DEV:/etc/resolv.conf" >/dev/null 2>&1 || true +sudo e2cp "$HOSTNAME_TMP" "$DM_DEV:/etc/hostname" >/dev/null 2>&1 || true +sudo e2cp "$HOSTS_TMP" "$DM_DEV:/etc/hosts" >/dev/null 2>&1 || true + +# TAP +log "creating tap device $TAP_DEV" +TAP_USER="${SUDO_UID:-$(id -u)}" +TAP_GROUP="${SUDO_GID:-$(id -g)}" +sudo ip tuntap add dev "$TAP_DEV" mode tap user "$TAP_USER" group "$TAP_GROUP" +sudo ip link set "$TAP_DEV" master "$BR_DEV" +sudo ip link set "$TAP_DEV" up +sudo ip link set "$BR_DEV" up + +log "starting firecracker process" +rm -f "$API_SOCK" +nohup sudo -E "$FC_BIN" --api-sock "$API_SOCK" >"$LOG_FILE" 2>&1 & +FC_PID="$!" + +log "waiting for firecracker api socket" +for _ in $(seq 1 200); do + [[ -S "$API_SOCK" ]] && break + sleep 0.02 +done +[[ -S "$API_SOCK" ]] || { log "firecracker api socket not ready"; exit 1; } + +log "configuring machine" +/usr/bin/sudo /usr/bin/curl --unix-socket "$API_SOCK" -X PUT http://localhost/machine-config \ + -H "Content-Type: application/json" \ + -d "$(jq -c '."machine-config"' "$VM_JSON")" >/dev/null + +boot_args="$(jq -r '."boot-source".boot_args' "$VM_JSON")" +boot_args="$(printf '%s' "$boot_args" | sed -E 's/(^| )hostname=[^ ]+//g; s/(^| )ip=[^ ]+//g' | awk '{$1=$1; print}')" +boot_args="$boot_args ip=${GUEST_IP}::${BR_IP}:255.255.255.0::eth0:off:${DNS_SERVER}" +boot_args="$boot_args hostname=$(jq -r '.name // empty' "$META_JSON")" + +log "configuring boot source" +/usr/bin/sudo /usr/bin/curl --unix-socket "$API_SOCK" -X PUT http://localhost/boot-source \ + -H "Content-Type: application/json" \ + -d "{ + \"kernel_image_path\": \"$KERNEL\", + \"boot_args\": \"$boot_args\" + }" >/dev/null + +log "attaching drives" +/usr/bin/sudo /usr/bin/curl --unix-socket "$API_SOCK" -X PUT http://localhost/drives/rootfs \ + -H "Content-Type: application/json" \ + -d "{ + \"drive_id\": \"rootfs\", + \"path_on_host\": \"$DM_DEV\", + \"is_root_device\": true, + \"is_read_only\": false + }" >/dev/null + +/usr/bin/sudo /usr/bin/curl --unix-socket "$API_SOCK" -X PUT http://localhost/drives/home \ + -H "Content-Type: application/json" \ + -d "{ + \"drive_id\": \"home\", + \"path_on_host\": \"$HOME_PATH\", + \"is_root_device\": false, + \"is_read_only\": false + }" >/dev/null + +/usr/bin/sudo /usr/bin/curl --unix-socket "$API_SOCK" -X PUT http://localhost/drives/var \ + -H "Content-Type: application/json" \ + -d "{ + \"drive_id\": \"var\", + \"path_on_host\": \"$VAR_PATH\", + \"is_root_device\": false, + \"is_read_only\": false + }" >/dev/null + +log "configuring network interface" +/usr/bin/sudo /usr/bin/curl --unix-socket "$API_SOCK" -X PUT http://localhost/network-interfaces/eth0 \ + -H "Content-Type: application/json" \ + -d "{ + \"iface_id\": \"eth0\", + \"host_dev_name\": \"$TAP_DEV\" + }" >/dev/null + +log "starting virtual machine" +/usr/bin/sudo /usr/bin/curl --unix-socket "$API_SOCK" -X PUT http://localhost/actions \ + -H "Content-Type: application/json" \ + -d '{ "action_type": "InstanceStart" }' >/dev/null +VM_STARTED=1 + +CREATED_AT="$(date -Iseconds)" +jq \ + --arg pid "$FC_PID" \ + --arg created_at "$CREATED_AT" \ + '.pid=$pid | .created_at=$created_at' \ + "$META_JSON" > "$META_JSON.tmp" && mv "$META_JSON.tmp" "$META_JSON" + +VM_CONFIG_JSON="$(/usr/bin/sudo /usr/bin/curl --unix-socket "$API_SOCK" -sS http://localhost/vm/config)" +jq '.' <<<"$VM_CONFIG_JSON" > "$VM_JSON" + +log "restored"