virt-manager not giving rtl8139 as option when qemu does?

eccerr0r

I've been using rtl8139 as the network card emulator on one of my hypervisor machines and the latest virt-manager/qemu update no longer worked for network on an existing virt-manager VM. Normally I netboot the VM and while firmware was able to PXE the correct image, grub and the kernel loaded did not understand the network.
So I went through the options of virt-manager gui, seems to now support only e1000e or virtio. The VM I have, its kernel does not support e1000e, nor do I think grub knows anything about it, but it was working when I last used. So I was baffled why QEMU no longer works.

That is until I tried manually typing rtl8139 in the nic field of virt-manager. Now it works.

I wonder why virt-manager doesn't show rtl8139 as a nic option when creating a VM? Or is it another package that offers the nic options that qemu provides?

app-emulation/virt-manager-4.1.0-r1
app-emulation/libvirt-10.10.0-r1
app-emulation/qemu-9.1.2
_________________
Intel Core i7 2700K/Radeon R7 250/24GB DDR3/256GB SSD
What am I supposed watching?

Anon-E-moose · Posted: Sat Mar 22, 2025 10:40 am Post subject:

I haven't played with libvirt/virt-manager in a long time, as I prefer the qemu cmdline,
but I would think that the problem is either libvirt or virt-manager aren't offering the (valid) option.
As to why. *shrugs*

szatox · Advocate Joined: 27 Aug 2013 Posts: 3603

If qemu still offers this NIC, you should be able to use it by editing xml config directly, whether virt-manager likes it or not.
I think this one uses full hardware emulation though, which is very very resource intensive and results in poor performance. Sure, poor performance is still better than nothing at all, so you might give it a shot if updating your pxe kernel is too much work.
_________________
Make Computing Fun Again

eccerr0r · Posted: Sat Mar 22, 2025 4:44 pm Post subject:

I was about to recompile the kernel to bloat it more with e1000 and virtio but wanted to keep the generic kernel relatively small (for both VMs and baremetal machines being bootstrapped.)

So yes afaik qemu still provides rtl8139 emulation but seems probably libvirt or virt-manager somehow not detecting this capability as it was before. Now that I have a few physical real e1000's I may have to include this in my generic kernel anyway...
_________________
Intel Core i7 2700K/Radeon R7 250/24GB DDR3/256GB SSD
What am I supposed watching?

egberts · Posted: Sun Mar 23, 2025 9:45 pm Post subject: