rc.conf - setting interface UP without IP-address?

Pavel Jordák pavel.jordak at siemens.com
Wed Aug 31 11:57:51 GMT 2005

On 31 Srpen 2005, 11:02, Ewald Jenisch napsal(a):
> Hi,
> I'm looking for a way to set an interface UP using /etc/rc.conf
> without giving the interface an IP-address (i.e. neither static nor DHCP)
> Background: The machine in question has three Ethernet-IFs - one
connects to the LAN (and has an IP-address) the other two are used for
monitoring traffic via ethereal only. For security reasons I don't want
to assign IP-addresses to the two "ethereal-only" interfaces - but I
need them "UP".
> Sure enough I can "up" these interfaces manually but I want them up at
> I've tried with entries like e.g.
> ifconfig_fxp1=""
> ifconfig_fxp1="UP"
> in my /etc/rc.conf - none of these work.
> So what should I configure in /etc/rc.conf in order to get the
> interfaces UP?
> BTW - ethereal only recognizes interfaces that are in the "UP" state.
> Thanks much in advance for any clue,
> -ewald

Hi, Ewald,

I'd try this:

ifconfig_fxp1="inet netmask"

It's not exactly, what you ask for, but could help. I'm not able to test
it now, it's only an idea...

Pavel Jordak
ANF DATA, Prague

More information about the freebsd-questions mailing list