# How to use Mender-Convert to convert container image?

**URL:** <https://hub.mender.io/t/how-to-use-mender-convert-to-convert-container-image/5860>\
**Category:** General Discussions\
**Created:** [May 24, 2023, 7:15pm UTC](https://hub.mender.io/t/how-to-use-mender-convert-to-convert-container-image/5860 "2023-05-24T19:15:14Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![numanames](https://yyz2.discourse-cdn.com/flex036/user_avatar/hub.mender.io/numanames/32/1911_2.png) [@numanames](https://hub.mender.io/u/numanames)\
**Post date:** [May 24, 2023, 7:15pm UTC](https://hub.mender.io/t/how-to-use-mender-convert-to-convert-container-image/5860/1 "2023-05-24T19:15:15Z")

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Hello everyone, I have been slowly but surely figuring out how this whole Mender thing works. I am currently in the process of converting a .img file after it has been created using dd. I am currently using a VMWare Ubuntu 22 virtual machine for this, but my end goal is to have this running on many desktop computers around the world, which will essentially work as servers.

I am confused on this specific step.

> **[Convert a Mender Debian image | Mender documentation](https://docs.mender.io/operating-system-updates-debian-family/convert-a-mender-debian-image#use-the-mender-convert-container-image)**

# move overlay to the input folder

mkdir -p input/overlay  
mv \<PATH\_TO\_MY\_OVERLAY\>/\* input/overlay/\*

# convert the image

MENDER\_ARTIFACT\_NAME=release-1 ./docker-mender-convert   
–disk-image input/golden-image-1.img   
–config configs/raspberrypi3\_config   
–overlay input/rootfs\_overlay\_demo/

First off, what is the overlay? I can’t find this mentioned anywhere else and am unsure what it is referring to.

–disk-image - This seems to just be the name of the disk image, simple enough.  
–config - What would this be for a Debian based OS? I am not using Raspberry PIs in my setup at all.  
–overlay input/rootfs\_overlay\_demo/ - I am confused on to what this is referring to.

My main question is figuring out what the overlay is. Could anyone guide me in the right direction? Thank you.

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**Author:** ![TheYoctoJester](https://yyz2.discourse-cdn.com/flex036/user_avatar/hub.mender.io/theyoctojester/32/1444_2.png) [@TheYoctoJester](https://hub.mender.io/u/TheYoctoJester)\
**Post date:** [May 25, 2023, 1:40pm UTC](https://hub.mender.io/t/how-to-use-mender-convert-to-convert-container-image/5860/2 "2023-05-25T13:40:38Z")

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Hi @numanames,

nice to hear you’re making progress! Hope this helps you to proceed:

- for a generic x86 linux distribution, you would start with [this](https://github.com/mendersoftware/mender-convert/blob/master/configs/generic_x86-64_hdd_config)
- the disk image is the binary image (as created via `dd`) of your golden device.
- the overlay is essentially a file hierarchy that gets added to the resulting image. The [README](https://github.com/mendersoftware/mender-convert#example-usage-raspberry-pi-3-raspbian-32bit) gives some examples of preparing overlays for using Hosted Mender, a demo server or a tenant token. Those should pretty much directly apply to x86 too.

Greetz,  
Josef

EDIT: fixed link @numanames

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<div class="post-metadata">

**Author:** ![numanames](https://yyz2.discourse-cdn.com/flex036/user_avatar/hub.mender.io/numanames/32/1911_2.png) [@numanames](https://hub.mender.io/u/numanames)\
**Post date:** [May 25, 2023, 3:55pm UTC](https://hub.mender.io/t/how-to-use-mender-convert-to-convert-container-image/5860/3 "2023-05-25T15:55:15Z")

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Hello, thank you for your reply. I believe the first link you sent is broken as it doesn’t open anything for me. I am looking into the readme link you provided now.