/dev/bpf0 ?????
Nicholas Buckley
Today on a Bull EPC400 cluster running AIX 4.3.1 I unearthed the following
entries in /dev
>ls -l /dev/bp*
> cr-------- 1 root system 56, 0 Jul 14 1999 /dev/bpf0
> cr-------- 1 root system 56, 1 Jul 14 1999 /dev/bpf1
> cr-------- 1 root system 56, 2 Jul 14 1999 /dev/bpf2
> cr-------- 1 root system 56, 3 Jul 14 1999 /dev/bpf3
Anyone recognise them, because we sure as hell don't !!!
Regards,
Nick Buckley
AIX Administrator,
NCM,
Cardiff,
Wales,
United Kingdom
e-mail: nicholas...@ncmgroup.com
(Please note: all newsgroup offerings are made in a personal
capacity and in no way are the responsibility of my employer)
p.s. Did you know that "AIX Operating System" is an anagram of "Mega sexy
partitions" !!!
Jens-Uwe Mager
>Today on a Bull EPC400 cluster running AIX 4.3.1 I unearthed the following
>entries in /dev
>
>>ls -l /dev/bp*
>> cr-------- 1 root system 56, 0 Jul 14 1999 /dev/bpf0
>> cr-------- 1 root system 56, 1 Jul 14 1999 /dev/bpf1
>> cr-------- 1 root system 56, 2 Jul 14 1999 /dev/bpf2
>> cr-------- 1 root system 56, 3 Jul 14 1999 /dev/bpf3
>
>Anyone recognise them, because we sure as hell don't !!!
These are the Berkeley Packet Filter devices used by tcpdump.
--
Jens-Uwe Mager <pgp-mailto:62CFDB25>
James Carlson
> >Anyone recognise them, because we sure as hell don't !!!
>
> These are the Berkeley Packet Filter devices used by tcpdump.
They're a little funny, too. They don't show up in /dev until tcpdump
has been used at least once since boot. Makes them a little annoying
if you want to use bpf for other programs such as dhcp ...
--
James Carlson, System Architect <car...@ibnets.com>
IronBridge Networks / 55 Hayden Avenue 71.246W Vox: +1 781 372 8132
Lexington MA 02421-7996 / USA 42.423N Fax: +1 781 372 8090
"PPP Design and Debugging" --- http://people.ne.mediaone.net/carlson/ppp
Jens-Uwe Mager
>j...@anubis.han.de (Jens-Uwe Mager) writes:
>> >Anyone recognise them, because we sure as hell don't !!!
>>
>> These are the Berkeley Packet Filter devices used by tcpdump.
>
>They're a little funny, too. They don't show up in /dev until tcpdump
>has been used at least once since boot. Makes them a little annoying
>if you want to use bpf for other programs such as dhcp ...
Yes, but from what I understand they do not want application programs to
use them. AIX has its own AF_NDD style socket mechanism that can be
used to do things like DHCP.
Nicholas Buckley
By coincidence, we created a VG with Major Number 56 ( same as these
devices ) on another node.
We could not synchronise HACMP because these devices were also MAJ=56.
So, we exported an re-imported the VG on its host node with a
non-conflicting MAJNO.
That solved that problem, but to end this thread, Jens/James, can you think
of a good reason why we shouild NOT remove these devices ??
And finally, they don't show up via lsdev -C, so can we just rm them ?
Nick.
Jens-Uwe Mager wrote in message ...
Jens-Uwe Mager
>By coincidence, we created a VG with Major Number 56 ( same as these
>devices ) on another node.
>
>We could not synchronise HACMP because these devices were also MAJ=56.
This looks like a bug to me, I would recommend to submit that as a bug
to your IBM support channel. There should be no way to create such a
major number conflict accidently.
>So, we exported an re-imported the VG on its host node with a
>non-conflicting MAJNO.
>
>That solved that problem, but to end this thread, Jens/James, can you think
>of a good reason why we shouild NOT remove these devices ??
>
>And finally, they don't show up via lsdev -C, so can we just rm them ?
This devices will come back as soon as someone uses the tcpdump command.
I would believe IBM should fix this so these bpf devices are first class
citizens in the AIX device configuration architecture or remove them.
I would actually prefer if they could extend the AF_NDD mechanism to
contain the equivalent of the packet filter engine, these would be much
cleaner architecture wise compared to putting it into a character device
(Linux does this, for example).
Dave Marquardt
> j...@anubis.han.de (Jens-Uwe Mager) writes:
> > >Anyone recognise them, because we sure as hell don't !!!
> >
> > These are the Berkeley Packet Filter devices used by tcpdump.
>
> They're a little funny, too. They don't show up in /dev until tcpdump
> has been used at least once since boot. Makes them a little annoying
> if you want to use bpf for other programs such as dhcp ...
We don't support using BPF for anything except tcpdump. That's why
the devices aren't there until you run tcpdump.
-Dave
James Carlson
> We don't support using BPF for anything except tcpdump. That's why
> the devices aren't there until you run tcpdump.
It would be nice to have a way to configure them in on start-up, since
they're useful for application programs even if no other IBM-supplied
program uses them.
Currently, I do "/usr/sbin/tcpdump -d host 0" in my /etc/rc.tcpip in
order to get them in place without actually dumping anything. That's
a little hackish ...