How to communicate 2 guest machines over serial in qemu?

How to communicate 2 guest machines over serial in qemu?

[Sidhartha Reddy Kaliki]

Hi,

We have 2 independent devices running openbmc software on each of
them. These devices can communicate with each other over a serial line
using SLIP protocol. Now we would like to emulate the same using qemu.

Do we have any provision to communicate 2 guest machines over a serial
interface using SLIP protocol?

We have tried a few options which are not helpful to solve our purpose.
It will be really helpful if you can provide us some guidance on this.

Thanks

Re: How to communicate 2 guest machines over serial in qemu?

[Alex Bennée]

Sidhartha Reddy Kaliki <sidhartha@drut.io> writes:

> Hi,
>
> We have 2 independent devices running openbmc software on each of
> them. These devices can communicate with each other over a serial line
> using SLIP protocol. Now we would like to emulate the same using qemu.
>
> Do we have any provision to communicate 2 guest machines over a serial
> interface using SLIP protocol?

You can connect the two chardev backends to each other. One will want to
be a server, the other a client. You can use pipe, socket or network
backends to do this.

> We have tried a few options which are not helpful to solve our purpose.
> It will be really helpful if you can provide us some guidance on this.

What have you tried so far?

>
> Thanks


-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro

Re: How to communicate 2 guest machines over serial in qemu?

[Sidhartha Reddy Kaliki]

we tried of working on socket and pipes,

In the original hardware, We have 2 compute modules. A serail
interface is available between them and we run a SLIP protocol in
software for the communication.

We would like to replecate the same in Qemu environment. In our
scenario the machine A and a machine B both runs the same software
image, they both should communicate over a SLIP protocol.
We tried using pipes but we are not sure how to communicate between 2
Virtual machines using them.

We appreciate a solution to communicate between Machine A and B using
pipe or by establishing a SLIP protocol between the machines.
Is there any way to establish a pipe between master and slave machine ?

On Tue, May 16, 2023 at 8:20 PM Alex Bennée <alex.bennee@linaro.org> wrote:
>
>
> Sidhartha Reddy Kaliki <sidhartha@drut.io> writes:
>
> > Hi,
> >
> > We have 2 independent devices running openbmc software on each of
> > them. These devices can communicate with each other over a serial line
> > using SLIP protocol. Now we would like to emulate the same using qemu.
> >
> > Do we have any provision to communicate 2 guest machines over a serial
> > interface using SLIP protocol?
>
> You can connect the two chardev backends to each other. One will want to
> be a server, the other a client. You can use pipe, socket or network
> backends to do this.
>
> > We have tried a few options which are not helpful to solve our purpose.
> > It will be really helpful if you can provide us some guidance on this.
>
> What have you tried so far?
>
> >
> > Thanks
>
>
> --
> Alex Bennée
> Virtualisation Tech Lead @ Linaro