[Testbed-admins] network drivers in freebsd.newnode MFS?

[Chaos Golubitsky <chaos@bbn.com>]

Okay, i fully expect to need to RTM on this one, and you're going
to have to bear with me, since it's been a long time since i did
anything serious with FreeBSD, and i've forgotten how it works...

So: i'm still trying to build my emulab here.  I picked a Dell R210
as my stock node because we have several, and the fewer distinct
types of node i have to configure, the easier.  I customized some
MFSes, setup a pcr210 node type, configured the BIOS of Node 1 to
PXE boot, and off i went.  However, while the node successfully
requests its files and boots, it never checks in to the server,
and if i login to the newnode MFS console and do an "ifconfig", i
see that i have only lo0.

I immediately suspect that the new shiny drivers on the R210 aren't
present in emulab's default MFS.  And, indeed, 'pciconf -lv' [1]
+ google suggests that i have two Intel NICs which want driver igb,
and two NICs with ungoogleable chip number (they're Broadcom BCM5716,
as it turns out, and thus probably want driver bce).

So, two questions:
(1) Does "newnode MFS is missing drivers i need for my hardware"
    sound like the right diagnosis of the problem?
(2) Is there an idiot's guide to adding drivers to emulab's MFSes
    (Add stuff to loader.conf.orig and stick a tarball somewhere?
    Compile a driver?  Compile a kernel?  I just don't have a good
    sense of how involved this should be)?  If not, i can poke
    through FreeBSD docs and figure it out, but i like to occasionally
    try to learn from other people's experiences as well as my own.

Chaos

[1] Output, for the not-easily-bored:
# pciconf -lv
...
none6@pci1:0:0: class=0x20000 card=0xa04c8086 chip=0x10c98086 rev=0x01 hdr=0x00
  class    = network
  subclass = ethernet
none7@pci1:0:1: class=0x20000 card=0xa04c8086 chip=0x10c98086 rev=0x01 hdr=0x00
  class    = network
  subclass = ethernet
none8@pci2:0:0: class=0x20000 card=0x02a51028 chip=0x163b14e4 rev=0x20 hdr=0x00
  class    = network
  subclass = ethernet
none9@pci2:0:1: class=0x20000 card=0x02a51028 chip=0x163b14e4 rev=0x20 hdr=0x00
  class    = network
  subclass = ethernet
...