Re: [Qemu-discuss] How to set the network card for qemu to use?

[Aleksei]

This is not the right mailing list to ask about persistent NIC naming on your host system.

Assuming you've solved that and trying to get a VM working with eth1, do the following:

1) Set up a bridge on the host (let's say it's bridge0) with eth1 as a slave. bridge0 is configured to auto-get IPv4 address via DHCP. Different methods are described here https://wiki.archlinux.org/index.php/Network_bridge.

2) Include the following to your Qemu command line. You don't need to manually create tap devices on the host, qemu-bridge-helper script does this for you.
    -device virtio-net,netdev=internet \
    -netdev bridge,br=bridge0,id=internet,helper=/usr/lib/qemu/qemu-bridge-helper

3) Start VM, post results. Please try to be concise ;) and post what you are trying to do and actual error messages. Also provide your Qemu version.
    

--Regards, Aleksei

---

From: Miroslav Rovis
Sent: Friday, October 14, 2016 7:47AM
To: Qemu-discuss
Subject: Re: [Qemu-discuss] How to set the network card for qemu to use?

On 161014-03:11+0200, Miroslav Rovis wrote:
...

Concrete setup is three NIC cards:
eth0
eth1
eth2

And the question is simple: what -netdev options (or is there some other
way?) do I use to get qemu to use eth2?

And that proved, to me, impossible.

I think I should try and maybe get the NIC that I connect to internet
with to get the name eth0 instead of the above.

...
And I thought of adding this line to kernel command line in grub.cnf :

netdev=21,,0x000000000001d000,,eth0

(and report back if that was, by some odd chance, successful)

Here's the way I gone through, it has concluded, you'll see why I'm
posting it. Following is a text already previously written, all is
over by now here....

---
One unsuccessful attempt, similar to mine, that I found:

https://lkml.org/lkml/2005/3/10/213
(notice it's a company, and nobody replied)

Also I found this old thread:

https://www.mail-archive.com/address@hidden/msg13466.html
(which I, in the end, haven't read, there were other tries there... but
likely the result was similar or same to mine)

Similar solutions offered at:

http://unix.stackexchange.com/a/10260

(
full reqest uri (clean):
http://unix.stackexchange.com/questions/10254/how-to-change-the-order-of-the-network-cards-eth1-eth0-on-linux

It's very much worth noticing that there are some fine explanations there,
but part of those explanations look very much to be obsolete stuff --
year 2011
)

where the suggestion reads:

netdev=irq=2,name=eth0

( of course, changing it to:

netdev=irq=21,name=eth0 )

Maybe that should do.

So instead of what I first thought:

netdev=21,,0x000000000001d000,,eth0

I think I should try:
netdev=irq=21,mem_start=0x000000000001d000,name=eth0

In the end I tried all of the above, and nothing worked. But nothing
nothing nothing. The kernel behaved as if there wasn't that line at all
(other then printing it in the logs).

I said further above: You'll see why I'm posting it. And it's because
this is probably impossible to do, and the kernel-parameters.txt should
probably be revises, at least for some ethernet cards.

It is probably that I have to use a different card, one that is eth0 on
every boot if I want qemu with pass-through.

Curiosity still lives here. If there were any successes in getting those
parameters to work, or if there are more explanations, I'll be glad to
here!

Regards!