avahi daemon uses a lot of CPU when network is not availiable

Hi Denis,

Unfortunately this bug report isn't too helpful to us as there are no more details.

Is this a common problem you see? Does it happen every time? Once off?

Thanks,
Trent

Hi. Yes, I understand this isn't too helpful, but I have no idea what else I can tell about this bug. It happens every time when system boots up with wi-fi switched off and ethernet cable is physically disconnected. It's 100% reproducible.

Here is my /etc/network/interfaces file

auto lo
iface lo inet loopback

auto airnet
iface airnet inet ppp
pre-up ip link set eth0 up
provider airnet

iface eth0 inet static
address 192.168.128.161
netmask 255.255.0.0

auto eth0

As you can see I have a pptp connection named airnet set up at start up. Maybe the problem is somehow concerned with that.

Is this still occurring in Ubuntu 8.10 or 9.04?

This still occurring in Ubuntu 8.10 (powerpc). I don't know on other platforms.

Could reproduce this in Karmic (x86 and Dove).

Still there in 10.10.

Are the Ubuntu Avahi packagers even aware of this serious bug which causes 100% cpu usage?

"daemon infinite loop triggered by an empty UDP packet"

https://bugzilla.redhat.com/show_bug.cgi?id=667187

J G Miller: That patch is in Natty

I suspect they are actually unrelated to the (?)DNS timeout(?) of this bug, but for the 100% cpu use on null UDP packet bug see also #655835 and #546231.

(if Denis has no network, there's small chance someone has sent him a null packet, and I think(?) this bug report predates the avahi patch which caused that null packet DoS situation. at least two different things going on here)

Hamish

If this is still happening, can you capture an strace log on the process?