help debug bwn(4) wireless

Robert Bonomi bonomi at
Sat May 5 21:03:21 UTC 2012

Anton Shterenlikht <mexas at> wrote;

> I'm afraid I understand very little
> from what you've written. Sorry
> to be such a shmuck. I've read a couple
> of books on networking, someting like
> Patterson & Hennesy (?) Networking - system
> approach (?), but I still find
> the whole networking area perfectly
> impenetrable. (If you can recommend
> a really introductory book on the
> subject, I'd really appreciate it.

The following books are *NOT* easy reading, but will teach you
nearly everything about how networking works:
   'TCP/IP illustrated'  Volumes 1 and 2  (3 is optional)
   "Internetworking with TCP/IP'  Volumes 1 and 2 (3 is 'programming')
These are the 'bibles' that virtully every professional has on 
their reference shelf (becaue they cover *everythig* from the
very basics up), along with 'Unix Network Programming', which gets 
into the nitty-gritty details of the internals of writing software 
that communicates over the network.

See also "TCP/IP Network Administration".  This is an "O'Reilley Associates"
book.  Virtually *everything* they publish is excellent.  If they've 
ever published an even mediocre book, _I_ have never encountered it.

For 'minimalist'/'simplistic' descriptions of specific terms,  see:

Google for 'unix glossary of terms' for attidional useful wordists.

> So, what I did is I disabled bge
> completely, i.e. removed from /etc/rc.conf,
> and I remembered to include wlan0 in
> /etc/ipf.rules. This works ok.

AH, if it is an 'either/or' situation, then
life is a lot simpler.

The 'ifconfig -a' output showed that _both_ interfaes were 
configured, "UP", with an IP address, *AND* that _both_ were
connected to 'something'.  

Using both interfaces at the same time is significantly more
complicated.  'Doable', just a bit tricky. And how you do it
depends on 'whiich way' is 'out' (to the rest of the world.)

> I'll need to think of an easy system
> to switch from bge to bwn. I usually
> use bge with static ip address at work
> and I'm trying to use bwn at home.

Write two simple shell sripts.  One that doess the 
things you just did to 'remove' bge0, and enable bwn0/wlan0.

And another that removes the bwn0/wlan0 references and adds 
the bge0 stu back in.

If you're doing this by manipulating the rc.conf 
settings, then you can even stick an automatic reboot 
in the end of each of those scripts.

If you turn on the machine and it comes up in the 'wrong' 
configuration, just run the script to change to the 
'other' one.  And reboot, if the script doesn't do it
for you.

When you have a better understanding of networking, and
the the basic networking configuration commands ('ifconfig'
and 'route', primarily), you can write scripts that make
the operational changes -without- needing to reboot.  Then
you can leave the 'boot' configuration at whatever you 
'normally' use (probably 'work'), and run the 'wireless'
script to take down the ethernet ad bring up the Wi-Fi.

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