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set -eu
[ -e hello-vmlinux.bin ] || wget https://s3.amazonaws.com/spec.ccfc.min/img/hello/kernel/hello-vmlinux.bin
[ -e hello-rootfs.ext4 ] || wget -O hello-rootfs.ext4 https://raw.githubusercontent.com/firecracker-microvm/firecracker-demo/ec271b1e5ffc55bd0bf0632d5260e96ed54b5c0c/xenial.rootfs.ext4
[ -e hello-id_rsa ] || wget -O hello-id_rsa https://raw.githubusercontent.com/firecracker-microvm/firecracker-demo/ec271b1e5ffc55bd0bf0632d5260e96ed54b5c0c/xenial.rootfs.id_rsa
TAP_DEV="fc-88-tap0"
# set up the kernel boot args
MASK_LONG="255.255.255.252"
MASK_SHORT="/30"
FC_IP="169.254.0.21"
TAP_IP="169.254.0.22"
FC_MAC="02:FC:00:00:00:05"
KERNEL_BOOT_ARGS="ro console=ttyS0 noapic reboot=k panic=1 pci=off nomodules random.trust_cpu=on"
KERNEL_BOOT_ARGS="${KERNEL_BOOT_ARGS} ip=${FC_IP}::${TAP_IP}:${MASK_LONG}::eth0:off"
ip link del "$TAP_DEV" 2> /dev/null || true
ip tuntap add dev "$TAP_DEV" mode tap
sysctl -w net.ipv4.conf.${TAP_DEV}.proxy_arp=1 > /dev/null
sysctl -w net.ipv6.conf.${TAP_DEV}.disable_ipv6=1 > /dev/null
ip addr add "${TAP_IP}${MASK_SHORT}" dev "$TAP_DEV"
ip link set dev "$TAP_DEV" up
cat <<EOF > vmconfig.json
{
"boot-source": {
"kernel_image_path": "hello-vmlinux.bin",
"boot_args": "$KERNEL_BOOT_ARGS"
},
"drives": [
{
"drive_id": "rootfs",
"path_on_host": "hello-rootfs.ext4",
"is_root_device": true,
"is_read_only": false
}
],
"network-interfaces": [
{
"iface_id": "eth0",
"guest_mac": "$FC_MAC",
"host_dev_name": "$TAP_DEV"
}
],
"machine-config": {
"vcpu_count": 2,
"mem_size_mib": 1024,
"ht_enabled": false
}
}
EOF
firecracker --no-api --config-file vmconfig.json
@alexellis
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alexellis commented Mar 1, 2022

@jvns FYI there is a 404 on: [ -e hello-rootfs.ext4 ] || wget -O hello-rootfs.ext4 https://raw.githubusercontent.com/firecracker-microvm/firecracker-demo/ec271b1e5ffc55bd0bf0632d5260e96ed54b5c0c/xenial.rootfs.ext4

This has moved to an S3 bucket, see upstream if you want to keep this up to date.

@alexellis
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alexellis commented Mar 1, 2022

The JSON file now also appears to fail with firecracker 1.0 with:

2022-03-01T14:56:05.112106369 [anonymous-instance:main:ERROR:src/firecracker/src/main.rs:453] Configuration for VMM from one single json failed: Invalid JSON: unknown field `ht_enabled`, expected one of `vcpu_count`, `mem_size_mib`, `smt`, `cpu_template`, `track_dirty_pages` at line 24 column 16

Removing the ht_enabled field gets a bit further to:

[    0.091330] List of all partitions:
[    0.091665] No filesystem could mount root, tried: 
[    0.091666]  ext3
[    0.092067]  ext4
[    0.092217]  squashfs
[    0.092377] 
[    0.092733] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(254,0)
[    0.093341] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.14.55-84.37.amzn2.x86_64 #1
[    0.093893] Call Trace:
[    0.094086]  dump_stack+0x63/0x89
[    0.094335]  panic+0xdf/0x239
[    0.094557]  mount_block_root+0x27c/0x2af
[    0.094880]  ? set_debug_rodata+0x12/0x12
[    0.095181]  mount_root+0x65/0x68
[    0.095428]  prepare_namespace+0x12f/0x167
[    0.095783]  kernel_init_freeable+0x21a/0x247
[    0.096059]  ? rest_init+0xb0/0xb0
[    0.096059]  kernel_init+0x9/0x100
[    0.096059]  ret_from_fork+0x35/0x40
[    0.096059] Kernel Offset: disabled
[    0.096059] Rebooting in 1 seconds..

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