Swap fails to mount due to a race condition #1729
Description
Bug
Usually on the first run of ignition it fails with the swap device unit timing out. After that, if I power-cycle, on the second boot Ignition will go though without errors.
The problem seems to be due to a race condition where the boot disk preparation doesn't complete before the swap unit is expected to be there. Note that sometimes the bug doesn't happen, but usually it does.
Operating System Version
I am running ignition on the latest CoreOS version. The Ignition file was compiled from a Butane file on Linux with Butane version v0.18.0.
Ignition Version
2.16.2
Environment
I am running Ignition on bare metal on a Raspberry Pi 3 (it also happens on the Raspberry Pi 4) in Fedora CoreOS (38.20230918.3.2).
Expected Behavior
Mounting swap succeeds on first boot.
Actual Behavior
The swap device fails to mount causing the first boot to fail and present a recovery shell.
Reproduction Steps
- Run coreos-installer on an instance with two disks giving it the ignition file from below.
- Reboot
Other Information
The following ignition file can be used to reproduce this:
{
"ignition": {
"version": "3.4.0"
},
"passwd": {
"users": [
{
"name": "core",
"sshAuthorizedKeys": [
"ssh-ed25519 ...."
]
}
]
},
"storage": {
"disks": [
{
"device": "/dev/disk/by-id/coreos-boot-disk",
"partitions": [
{
"label": "root",
"number": 4,
"resize": true,
"sizeMiB": 8192
},
{
"label": "swap",
"number": 5,
"sizeMiB": 4096
}
],
"wipeTable": false
},
{
"device": "/dev/disk/by-id/usb-...",
"partitions": [
{
"label": "var",
"number": 1
}
],
"wipeTable": false
}
],
"filesystems": [
{
"device": "/dev/disk/by-partlabel/swap",
"format": "swap"
},
{
"device": "/dev/disk/by-partlabel/var",
"format": "ext4",
"path": "/var"
}
]
},
"systemd": {
"units": [
{
"contents": "# Generated by Butane\n[Swap]\nWhat=/dev/disk/by-partlabel/swap\n\n[Install]\nRequiredBy=swap.target",
"enabled": true,
"name": "dev-disk-by\\x2dpartlabel-swap.swap"
},
{
"contents": "# Generated by Butane\n[Unit]\nRequires=systemd-fsck@dev-disk-by\\x2dpartlabel-var.service\nAfter=systemd-fsck@dev-disk-by\\x2dpartlabel-var.service\n\n[Mount]\nWhere=/var\nWhat=/dev/disk/by-partlabel/var\nType=ext4\n\n[Install]\nRequiredBy=local-fs.target",
"enabled": true,
"name": "var.mount"
}
]
}
}
I didn't manage to reproduce this with a single disk, but due to it being a race condition and not always happening, I cannot say for certain it doesn't also happen without the separate var device.
The rdsosreport.txt looks like this.