[avahi] Resolving many ( > 200 ) items seems to lead to apparent congestion in the dbus

[Daniel Wynne]

Hi Lennart!

After a short interrupt I am back in avahi-business ;-)

PLaying around a little bit with parameters I boiled it down to 
AVAHI_CACHE_ENTRIES_MAX
OBJECTS_PER_CLIENT_MAX

These Parameters are slightly tight I think when it comes to bigger
networks i.e. more than 100 Services. 

You said these limitations are implemented to avoid misuse, i.e.
DOS-Attacks.

Do you think it is possible in future releases of Avahi to loosen these
limitations a little bit, to enable more comprehensive usage of Avahi,
even for professional applications like ours ;-)
DOS Attacks are way above the limitations of 500, even way above 5000. I
think when talking about DOS we are in millions and above.

What do you say?

Kind Regards

Daniel
 


On Sun, 2009-06-07 at 01:47 +0200, Lennart Poettering wrote:
> On Thu, 28.05.09 13:43, Daniel Wynne (daniel.wynne at mobotix.com) wrote:
> 
> > But I think thats exactly the problem in our case. In our Testnetwork 
> > reside about 250 cameras we want to find and resolve via Avahi. So the 
> > cache is way big enough. 
> 
> No. The limit of 500 entries in the cache that Avahi enforces is for
> RRs, not services or hosts.
> 
> For each service you need (at least) one A, one PTR one SRV and one
> TXT RR. Usually even more. I.e. if you register 250 services and want
> to browser for them all at the same time you need as absolute minimum
> space for 1000 entries, and practically even more.
> 
> Lennart
>