Choose an x86 image: combined, ext4, squashfs, EFI/BIOS

One-line choice

PVE default SeaBIOS: prefer generic-ext4-combined.img.gz (tested here);
UEFI/OVMF: choose a combined image with -efi;
factory-reset/read-only root + overlay: choose squashfs combined;
existing bootloader/partitions, replace rootfs only: use a rootfs image;
container/chroot: rootfs.tar.gz, not a disk image.

Read the filename

Main 25.12.6 x86/64 files:

openwrt-25.12.6-x86-64-generic-ext4-combined.img.gz
openwrt-25.12.6-x86-64-generic-ext4-combined-efi.img.gz
openwrt-25.12.6-x86-64-generic-squashfs-combined.img.gz
openwrt-25.12.6-x86-64-generic-squashfs-combined-efi.img.gz
openwrt-25.12.6-x86-64-generic-ext4-rootfs.img.gz
openwrt-25.12.6-x86-64-generic-squashfs-rootfs.img.gz
openwrt-25.12.6-x86-64-generic-kernel.bin
openwrt-25.12.6-x86-64-generic-targz-rootfs.tar.gz
openwrt-25.12.6-x86-64-rootfs.tar.gz

Three words matter:

Word	Meaning	If wrong
`combined`	whole-disk image with partition table/boot	using it as rootfs can overwrite partitions
`rootfs`	filesystem only	no bootloader; cannot boot directly
`ext4` / `squashfs`	writable root / read-only root + overlay	affects recovery/write behavior
`-efi`	UEFI boot	legacy BIOS may not boot it
`tar.gz`	rootfs archive	not a bootable disk image

ext4 vs squashfs

ext4 combined: writable root; common for VMs/soft routers; behaves like a normal Linux install.
squashfs combined: read-only root, config in overlay; better factory reset/anti-mistake; different space/maintenance.
Both can boot in PVE; this lab only tested ext4. Do not skip backups because “squashfs is safer”.

BIOS vs UEFI

PVE default SeaBIOS: use a combined image without -efi;
PVE OVMF (UEFI): use -efi combined and prepare an EFI disk;
Physical: check UEFI/Legacy in firmware and match;
Wrong choice: no boot entry, GRUB does not start, falls to PXE/BIOS.

This lab: PVE VM 200, SeaBIOS + generic-ext4-combined; booted successfully.

Download and verify

ComputerDownload image and sha256sums

curl -LO https://downloads.openwrt.org/releases/25.12.6/targets/x86/64/openwrt-25.12.6-x86-64-generic-ext4-combined.img.gz
curl -LO https://downloads.openwrt.org/releases/25.12.6/targets/x86/64/sha256sums
grep 'generic-ext4-combined.img.gz' sha256sums | sha256sum -c -

This lab: 13.0MB .img.gz, 120.5MB .img after decompression; SHA-256 matched.

ExpectedOfficial/TUNA source and checksum pass.

ComputerDecompress

gzip -dk openwrt-25.12.6-x86-64-generic-ext4-combined.img.gz
ls -lh openwrt-25.12.6-x86-64-generic-ext4-combined.img

sysupgrade and PVE qm importdisk use .img; do not write the .gz directly to disk.

ExpectedA .img ready for import/write.

Import into PVE

PVE hostImport disk and set boot order

qm create 200 --name openwrt --memory 512 --cores 2 --cpu host \
  --scsihw virtio-scsi-pci --ostype l26 --vga std --serial0 socket \
  --net0 virtio,bridge=vmbr0

qm importdisk 200 openwrt-25.12.6-x86-64-generic-ext4-combined.img local-lvm
qm set 200 --scsi0 local-lvm:vm-200-disk-0
qm set 200 --boot order=scsi0
qm start 200

If PVE uses UEFI/OVMF, use the -efi image and an EFI disk; do not force a BIOS image onto UEFI.

ExpectedVM boots from the imported disk, not ISO/PXE.

PVE hostVerify boot

qm terminal 200
# or inside the VM
ubus call system board
cat /etc/openwrt_release

This lab booted 25.12.6 x86/64; default LAN 192.168.1.1.

ExpectedConsole shows OpenWrt and the correct version/target.

Physical disk write

# verify the target first; do not copy the wrong device name
lsblk
sudo dd if=openwrt-...-combined.img of=/dev/sdX bs=4M status=progress conv=fsync
sync

dd overwrites the whole target; disconnect unrelated disks/verify the device;
For UEFI, choose -efi;
Boot from that disk; do not let the ISO keep boot priority;
Physical NIC names may not match PVE eth0/eth1; identify by MAC/PCI.

Common failures

PVE import will not boot

boot order is not scsi0;
you chose rootfs instead of combined;
BIOS/UEFI image mismatch;
disk bus/controller mismatch;
serial console not configured, no boot log.

Physical UEFI boot fails

non--efi image;
BIOS still in Legacy/CSM;
incomplete USB write;
Secure Boot/signature restrictions.

Original system disappeared after writing

dd wrote the wrong disk. Back up, verify lsblk size/model, then write; do not test on a production machine.

rootfs image will not boot directly

rootfs has no bootloader/partition table; use an existing bootloader or the appropriate container/virtualization path.

E2 lab run (2026-10-20)

Environment: PVE 9.2.2; OpenWrt 25.12.6 x86/64; generic-ext4-combined.img.gz; SeaBIOS.
Download: .img.gz 13.0MB; .img 120.5MB; SHA-256 matched official sha256sums.
PVE: qm importdisk → scsi0 → boot order=scsi0; VM booted 25.12.6.
Not tested: -efi/OVMF, squashfs, physical USB, Secure Boot, 24.10 image differences.
Recipe: tests/recipes/x86-image-25.12.md.

Sources and review

This is E2 partial: BIOS/ext4 combined + PVE import were tested; UEFI/squashfs/physical write were not.
Image names/availability change per release; use the download page.
No independent reviewer; conclusions are limited to this PVE/VM environment.

Sources

Router.Homes

Independent OpenWrt notes. Every page states the firmware, device, package manager and way back.

Icons: Solar by 480 Design, CC BY 4.0