Limiting the number of probed interfaces?

[Jeremy Chadwick]

On Thu, May 03, 2007 at 03:30:48PM +0200, Patrick M. Hausen wrote:
> On Thu, May 03, 2007 at 08:49:40AM -0400, Michael Proto wrote:
> > 
> > Would the following in /boot/device.hints achieve what you are after?
> > 
> > hint.bge.1.disabled="1"
> > hint.bge.2.disabled="1"
> 
> That would be the feature I am seeking. Unfortunately this
> had no effect. I already tried. The latest statement I was able
> to find via Google claimed, that for FBSD 5.2 "you cannot disable
> PCI devices other than completely removing the driver".
> I don't know if this has changed since then.

I don't think it has.  AFAIK you're somewhat out of luck here.  This is
one of the biggest complaints I have about vendors who piggyback IP
management (read: KVM-over-IP, LightOut, etc.) capabilities on an
existing ethernet port (and also why Compaq's iLO/iLO2 has a dedicated
port ;) ).

> According to Fujitsu Siemens support they use something called UMP,
> 'Universal Management Port', to send packets to the management
> processor via a shared Ethernet PHY.
> 
> In theory the OS should be able to use the NIC at the same time
> as the management processor. You can use either a true shared
> LAN for both or 802.1q to get both interfaces into seperate
> broadcast domains.

Correct.  However, the network driver in the operating system needs to
be aware of this fact and try to "play nice" with the existing
management framework.

I believe at present, Jung-uk Kim <jkim at FreeBSD.org> maintains
the bge(4) driver.  There has been mention as of late about this
loader option as well:

hw.bge.allow_asf="1"

On my systems sysctl -d claims this OID doesn't exist, so I'm
not sure what all it does.  But looking at the code:

SYSCTL_INT(_hw_bge, OID_AUTO, allow_asf, CTLFLAG_RD, &bge_allow_asf, 0,
        "Allow ASF mode if available");

> The problem with FreeBSD seems to be that bge_reset() which
> is called by bge_attach() clears the UMP configuration area.
> According to them Linux does not do this.

Linux likely has awareness of the management framework.  If this
is a major problem/show-stopper (and I can only speak for myself), I
would end up using Linux instead of FreeBSD.  It ultimately depends
on how important the feature is to you.

> Since I like a dedicated physical management interface much
> better, anyway, my final solution is rather simple:
> 
> In the BIOS setup program disable the LAN port on that interface
> while keeping the setting for "Management LAN" at "Enabled".
> 
> This has the desired effect: remote management works and FreeBSD
> doesn't see the port at all. Costs you a NIC, though ;-)

I understand what you're getting at.  I'm not sure how it "costs you a
NIC" though, since with those BIOS settings, essentially what you're
doing is making that NIC dedicated to remote management (which is how
it should be done anyways).

Sorry if this Email isn't much help; it's more of a "I feel your pain,
and this is why it's important to pick certain hardware vs. others"
Email.

-- 
| Jeremy Chadwick                                    jdc at parodius.com |
| Parodius Networking                           http://www.parodius.com/ |
| UNIX Systems Administrator                      Mountain View, CA, USA |
| Making life hard for others since 1977.                  PGP: 4BD6C0CB |