Hello,

I would like to deploy a small container on my RPI.
The OS is running in diskless mode (lbu) and I have a quite large data
partition which is read-only.
I use the data partition to store large stuff like node libraries.

By the way I was expecting to be able to start a container from this
read-only partition. As the container is immutable I don't see any reason
to make the partition rw, except of course when updating the docker image.
So does anyone tried (and hopefully succeeded) to run a container that way ?

Thank you.

If you're running just a container it should depend on what process you run
in the container... You wouldn't need to run "the os" necessarily, so using
read only would work if your process never writes to disk. In some cases
you might not need an os image at all.

On Tue, 9 Dec 2025, 01:26 Jerome Marc, <marcgruselle@gmail.com> wrote:

> Hello,
>
> I would like to deploy a small container on my RPI.
> The OS is running in diskless mode (lbu) and I have a quite large data
> partition which is read-only.
> I use the data partition to store large stuff like node libraries.
>
> By the way I was expecting to be able to start a container from this
> read-only partition. As the container is immutable I don't see any reason
> to make the partition rw, except of course when updating the docker image.
> So does anyone tried (and hopefully succeeded) to run a container that way ?
>
> Thank you.
>
>
>

I need an image. There is no problem running the process inside the
container in a read-only root. There are options for that. But even if the
guest is read-only, it doesn't mean that the container host can use a ro
filesystem. I guess that lxc could be more flexible for that.

Le mar. 9 déc. 2025 à 08:24, Guido Trotter <ultrotter@debian.org> a écrit :

> If you're running just a container it should depend on what process you
> run in the container... You wouldn't need to run "the os" necessarily, so
> using read only would work if your process never writes to disk. In some
> cases you might not need an os image at all.
>
> On Tue, 9 Dec 2025, 01:26 Jerome Marc, <marcgruselle@gmail.com> wrote:
>
>> Hello,
>>
>> I would like to deploy a small container on my RPI.
>> The OS is running in diskless mode (lbu) and I have a quite large data
>> partition which is read-only.
>> I use the data partition to store large stuff like node libraries.
>>
>> By the way I was expecting to be able to start a container from this
>> read-only partition. As the container is immutable I don't see any reason
>> to make the partition rw, except of course when updating the docker image.
>> So does anyone tried (and hopefully succeeded) to run a container that way ?
>>
>> Thank you.
>>
>>
>>

Sure, you're giving it an image, but what processes are you running within
that image? It all depends what your entry point and commands are, since
even if you give it the image it's not like you're "booting" Alpine to run
the container, just starting the process defined in the entry point....

Thanks,

Guido

On Tue, 9 Dec 2025, 09:33 Jerome Marc, <marcgruselle@gmail.com> wrote:

> I need an image. There is no problem running the process inside the
> container in a read-only root. There are options for that. But even if the
> guest is read-only, it doesn't mean that the container host can use a ro
> filesystem. I guess that lxc could be more flexible for that.
>
> Le mar. 9 déc. 2025 à 08:24, Guido Trotter <ultrotter@debian.org> a
> écrit :
>
>> If you're running just a container it should depend on what process you
>> run in the container... You wouldn't need to run "the os" necessarily, so
>> using read only would work if your process never writes to disk. In some
>> cases you might not need an os image at all.
>>
>> On Tue, 9 Dec 2025, 01:26 Jerome Marc, <marcgruselle@gmail.com> wrote:
>>
>>> Hello,
>>>
>>> I would like to deploy a small container on my RPI.
>>> The OS is running in diskless mode (lbu) and I have a quite large data
>>> partition which is read-only.
>>> I use the data partition to store large stuff like node libraries.
>>>
>>> By the way I was expecting to be able to start a container from this
>>> read-only partition. As the container is immutable I don't see any reason
>>> to make the partition rw, except of course when updating the docker image.
>>> So does anyone tried (and hopefully succeeded) to run a container that way ?
>>>
>>> Thank you.
>>>
>>>
>>>