Model: ChatGPT-5 Thinking
Question:
Is it possible to save a Linux machine state to disk, kind of like a sleep, boot a different system and when booting the system with the saved state resume from that saved state?
Short answer: yes, but only with strict caveats.
Linux “hibernate” (aka suspend-to-disk) writes RAM to swap, powers off, and later restores that exact state. You can boot another OS in between as long as the other OS does not touch anything the hibernated Linux had mounted or its swap. If that rule is broken you risk data loss or a failed resume. In practice, doing this repeatedly is fragile; using a VM is the robust alternative.
What must be true for dual-boot hibernate
Boot back into the same Linux (ideally the same kernel build) that created the image.
Do not mount or write (even accidentally) any partition that the hibernated Linux had mounted. Safer: don’t mount them at all from the other OS.
Use separate swap: the other OS must not use the swap partition/file that holds the hibernation image. (Per-OS swap is best.)
Encrypted swap: don’t use a random key. Use a persistent LUKS mapping so the initramfs can read the image.
No firmware/hardware changes between hibernate and resume (BIOS updates, GPU mode flips, moving disks, etc.).
Minimal setup (bare metal)
1. Ensure swap ≥ RAM (or configure compression).
2. Configure resume:
If using a swap partition: add to kernel cmdline, e.g.
resume=UUID=
If using a swapfile: also set the physical offset:
resume=UUID=
3. Rebuild initramfs (varies by distro) and update bootloader.
4. Test: systemctl hibernate → power on → confirm resume without booting another OS first.
5. Only then try booting the other OS, don’t mount the hibernated Linux’s partitions, then reboot back to the original Linux to resume.
Common pitfalls
Some distros disable hibernate by default or when swap is on a random LUKS key.
Shared swap between two Linux installs will clobber the image—use distinct swap per OS.
Windows Fast Startup/hibernation: turn it off; likewise don’t mount a hibernated Windows volume from Linux, and don’t let Windows write Linux filesystems.
Safer alternatives
Virtual machine snapshots/suspend (QEMU/KVM, VMware, VirtualBox): pause/save the VM state, run any other OS on the host, then restore—this is reliable and fast.
CRIU checkpoint/restore for specific services/containers (not full-machine state).
kexec is for switching kernels quickly, not for saving state across a full reboot.
If you tell me your distro, swap layout (partition vs file, encrypted or not), and whether the “other OS” is Windows or another Linux, I can give you exact commands for the resume parameters and initramfs steps.