device (ip/mac) address discovery

device (ip/mac) address discovery

Post by matt » Thu, 14 Apr 2005 12:15:23



Hi all, i need a bit of creative thinking...  (therefore I ask this on a
linux group)

I have an old managed hub i bought as salvage, and i'd like to start using
it's more advanced functions.

Here's the info on the device:
David Systems (a chipcom company...now i think 3com bought them)
ExpressNet secure high density workgroup hub (16 port)
model: 6370s
and i do have the management "plugin" for it.

here's what i need help with...
I assume this device can be managed with snmp/telnet/whatever so it must
have a MAC address and be abl to have an ip address set.  yes?

How can I determine (at least) it's MAC address?  it is not indicated on
the case, and i do not know what subnet it was last connected to.

--as an alternative, i can go through the serial management port--
BUT the one refrence i've found to this device online mentions that the
serial port isn't configured like a standard serial interface....

does anyone know the correct pin-out for the management port?

thanks to all that read this far,
+matt

 
 
 

device (ip/mac) address discovery

Post by Jack Master » Thu, 14 Apr 2005 16:11:56



> Hi all, i need a bit of creative thinking...  (therefore I ask this on a
> linux group)

> I have an old managed hub i bought as salvage, and i'd like to start using
> it's more advanced functions.

> Here's the info on the device:
> David Systems (a chipcom company...now i think 3com bought them)
> ExpressNet secure high density workgroup hub (16 port)
> model: 6370s
> and i do have the management "plugin" for it.

> here's what i need help with...
> I assume this device can be managed with snmp/telnet/whatever so it must
> have a MAC address and be abl to have an ip address set.  yes?

Possibly, but maybe it had some custom S/W for managing it.

Quote:> How can I determine (at least) it's MAC address?  it is not indicated on
> the case, and i do not know what subnet it was last connected to.

Don't think the MAC address alone will help a lot, you need an IP. Maybe
if you're very lucky it will respond to a broadcast ping. If not, try
nmap. Concentrate on the private IP ranges (10.x.x.x, 192.168.x.x etc)
first, most likely the management address sits in there somewhere.

Quote:> --as an alternative, i can go through the serial management port--
> BUT the one refrence i've found to this device online mentions that the
> serial port isn't configured like a standard serial interface....

> does anyone know the correct pin-out for the management port?

You can read this in two ways, one) the pin-out is non-standard, or two)
the pin-out might be standard, but it speaks some proprietary protocol
instead of something that a VT100 emulator can handle.

If you don't find the pin-out, it becomes trial and error....
If you have a RS-232 breakout box, preferably one with LED indicators on
it, it helps a lot, otherwise grab a soldering iron, and build a cable.
The trick is to find the TXD (outgoing from the hub), once you have
that, you can push some data to other pins and see if it echos. Start
measuring pins; ground can be assumed to be connected to chassis ground,
TXD should have a (if I remember correctly) negative voltage on it. Find
any pin with a defined voltage on it, and see if it sends out data when
you power-cycle the unit (it might send out a login prompt or a 'Hello
here I am' message. Once you have located TXD, hook it up to a
terminal(-emulator) and try to push data to one of the other pins to see
if it echoes.

Quote:

> thanks to all that read this far,
> +matt

hth
J.

 
 
 

device (ip/mac) address discovery

Post by matt » Fri, 15 Apr 2005 00:07:16



> Don't think the MAC address alone will help a lot, you need an IP. Maybe
> if you're very lucky it will respond to a broadcast ping. If not, try
> nmap. Concentrate on the private IP ranges (10.x.x.x, 192.168.x.x etc)
> first, most likely the management address sits in there somewhere.

well, i learned a trick when working with another device of mine that
dosn't come with any way to initial set an ip address:  you can set a
static arp entry in your arp table that associates the device's mac with
an ip (as far as your workstation is concerned).  then you can use that
ip to talk to the device.  kinda neat trick :)

Quote:> If you don't find the pin-out, it becomes trial and error.... If you
> have a RS-232 breakout box, preferably one with LED indicators on it, it
> helps a lot, otherwise grab a soldering iron, and build a cable. The
> trick is to find the TXD (outgoing from the hub), once you have that,
> you can push some data to other pins and see if it echos. Start
> measuring pins; ground can be assumed to be connected to chassis ground,
> TXD should have a (if I remember correctly) negative voltage on it. Find
> any pin with a defined voltage on it, and see if it sends out data when
> you power-cycle the unit (it might send out a login prompt or a 'Hello
> here I am' message. Once you have located TXD, hook it up to a
> terminal(-emulator) and try to push data to one of the other pins to see
> if it echoes.

thanks for the great info.  i don't have a breakout box, but i do have a
scope so i'll use that for my initial fishing around
Quote:> hth
> J.

 
 
 

device (ip/mac) address discovery

Post by matt » Fri, 15 Apr 2005 09:49:09



> If you don't find the pin-out, it becomes trial and error....
> If you have a RS-232 breakout box, preferably one with LED indicators on
> it, it helps a lot, otherwise grab a soldering iron, and build a cable.
> The trick is to find the TXD (outgoing from the hub), once you have
> that, you can push some data to other pins and see if it echos. Start
> measuring pins; ground can be assumed to be connected to chassis ground,
> TXD should have a (if I remember correctly) negative voltage on it. Find
> any pin with a defined voltage on it, and see if it sends out data when
> you power-cycle the unit (it might send out a login prompt or a 'Hello
> here I am' message. Once you have located TXD, hook it up to a
> terminal(-emulator) and try to push data to one of the other pins to see
> if it echoes.

Jack,
thanks again, i put the scope on it today, and learned what pins do what.
I'm not sure what the person who said it wasn't standard was talking
about, but everything looked standard to me, so i held my breath and
plugged in my handheld, fired up some terminal emulation software.
guessed it on the first try vt100 9600-8-n-1 :)

now my only problem is the password that stops me from doing anything
useful (see my next thread)

thanks again,
+matt

 
 
 

device (ip/mac) address discovery

Post by Bobber » Thu, 12 Jan 2006 19:30:03


matt would you mind posting the pinouts that you found.

I have a simular device/model. Volksnet LE109A. It doesnt have the mgmt port, but pop it open and it has all
sorts of hidden ports (one being the mgmt port i belive)

Thanks

--
Bobbert
------------------------------------------------------------------------
Bobbert's Profile: http://www.linuxarticles.com/forums/member.php?userid=7748
View this thread: http://www.linuxarticles.com/forums/showthread.php?t=52854

Posted at http://www.linuxarticles.com

 
 
 

1. WANTED: pingmac <IP ADDR> which returns <MAC ADDRESS of IP ADDRESS>

Hello!

I know this can be done by way of ping/arp at the solaris command line
or via a script, OR via system() calls.  Does anyone know of someone's
efforts to whip this up in an actual executable?  The goal of the
program is to work like this:


PINGMAC 137.204.192.19 (dilbert): MAC ADDRESS of dilbert is:
08:0e:10:02:12:1e


I know there are practical limitations like: MUST BE ON SAME SUBNET
and stuff like this.  BUT does anyone know of a pgm like this, or
might be able to point me somewhere that might?

Tx!

  -Scott

2. recplication

3. IP Masquerading with IP Address and Mac Address Restrictions

4. UNIX Trade Rags

5. How can I determine IP address of attached device without its MAC?

6. Configuration of Apache 1.1.1 w/SSL (pointer...)

7. Binding a single IP Address to two different MAC addresses

8. IP Masquerade & DNS lookup failure

9. Determining IP address from MAC address

10. MAC Address From IP Address

11. change MAC address can change IP address of a machine?

12. using mac address instead of an IP address of hostname

13. how to convert mac address to ip address