System-induced packetloss on FreeBSD 4.11?

[Ragnar Lonn]

Hi all,

Running FreeBSD 4.11, we have noticed that some operations done on one 
physical
network interface seems to cause packet drops on other interfaces on the 
system.

For example, starting a dhclient process on interface em0 will cause a 
few packets to
get dropped on the active interface em1. Doing "ifconfig em0 down ; 
ifconfig em0 up"
will also have the same effect.

Has anyone else experienced this and does anyone know why it happens?

It's not a major problem but it would be nice to know what causes it so 
we'll know
when to expect it as we're using the system for measurements of, among 
other things,
packet loss.

We're using Intel em(4) cards, on FreeBSD 4.11-RELEASE + Marko's network
stack virtualization patch.

Regards,

  /Ragnar