X86: an Alternative Solution to EXT 4 Root Partition Extension

My network layout:
ISP router in bridge mode ---> x86 Router (a ZOTAC ZBOX-CI620) ----> Dumb AP

Why am I posting this guide? I tried to use the OpenWRT guide, and others available on Youtube, on how to extend an ext4 root partition on my X86 router's SSD without success. I am hoping this guide helps someone who faces the same issue.

Challenge: Extending the root partition on the x86 machine's SSD with an OpenWRT EXT4 EFI image. The challenge was that following the OpenWRT guide for X86 partitioning (after OpenWRT 22.03) did not seem to result in the free space being allocated correctly. I needed the extra space since I run Adguard Home on the router which requires a fair amount more than the 100MB allocated by the default image's partition.

What you will need:
1.USB stick with enough space to run Ubuntu live.
2. A USB to SSD cable.
3. A PC able to run Ubuntu Live from a USB drive.


  1. Download and flash a USB Drive with Ubuntu Live.
  2. Connect the router's SSD to my main PC via USB cable.
  3. Configure PC's BIOS to run the Live USB at boot.
  4. Boot PC
  5. Use Live option of Ubuntu when given the option (the version that allows you to try Ubuntu before installing it)
  6. When you are in the Ubuntu OS, use the GParted application to extend the root partition on the OpenWRT SSD.
  7. Re-attach SSD to x86 router.
  8. Restart router.

When you access the router through the Luci GUI, the extended partition should reflect the extended root partition.

Save yourself some time next time, and go for the Gparted live image, should be a smaller DL, and faster boot too.


Thank you. I'll give it a go next time.