Interface working only after first packet is sent out ...

Hi,


I've been having an issue for a fairly long time, on several system
(either physical or virtual machine).

Basically I don't have network connectivity until the machine
initiates it's first packet out.

So let's say I just booted the machine (and it has no sw running on
it, just base system), if I try to ping it, it won't respond.
In a tcpdump on the interface, I can see the incoming ping, but not
outgoing responses.

Now from the machine itself, I generate a single ping to anywhere,
then everything will start working as expected and it will last
forever until the next reboot.

Has anyone ever seen something like this ?

Most of the time I don't notice it because either it's a desktop
machine and then even just a DHCP request makes it work from boot, or
even on server, the ntp daemon generates the first packet and it
works.

I don't know if it's a bug or if I'm doing something wrong somewhere,
but I really don't see what it could be ....



Cheers,

    Sylvain