8 nics limits on KVM ??

8 nics limits on KVM ??

[Yann Dupont]

Hello,

we are using kvm for wifidog, a wifi portal. In our case, we have lots 
of VLANS, and those vlans are connected  on separate bridges on the 
host. So, for the kvm machine running wifidog, we're having lots of 
virtual nics (more than 10). Launching kvm, we had this error mesage : 
Too many nics.

The limit seems hardcoded in qemu (in qemu/net.h), I've changed MAX_NICS 
from 8 to 24, and this seems to do the trick.

Is there any adverse effects doing this ? Is the limit arbitrary , or 
there for a good reason ?

Cheers,

-- 
Yann Dupont - Service IRTS, DSI Université de Nantes
Tel : 02.51.12.53.91 - Mail/Jabber : Yann.Dupont@univ-nantes.fr

Re: 8 nics limits on KVM ??

[Avi Kivity]

Yann Dupont wrote:
> Hello,
>
> we are using kvm for wifidog, a wifi portal. In our case, we have lots 
> of VLANS, and those vlans are connected  on separate bridges on the 
> host. So, for the kvm machine running wifidog, we're having lots of 
> virtual nics (more than 10). Launching kvm, we had this error mesage : 
> Too many nics.
>
> The limit seems hardcoded in qemu (in qemu/net.h), I've changed 
> MAX_NICS from 8 to 24, and this seems to do the trick.
>
> Is there any adverse effects doing this ? Is the limit arbitrary , or 
> there for a good reason ?

No good reason I can think of.  Qemu used to have only a few PCI slots, 
but now we have 32 (I think) so the limit can easily be raised.

-- 
error compiling committee.c: too many arguments to function