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Re: Remote target behind console server


At 12:33 AM 7/4/2002 -0400, Quality Quorum wrote:


On Wed, 3 Jul 2002, KONG, Gangfeng wrote:

>
> > >
> > > Hi,
> > >
> > > I start the gdb stub on the target by:
> > > gdbstart -s 38400 -t /dev/ttyS0
> > > and start the gdb on the development box by:
> > > gdb vmlinux
> > > gdb)
> > > gdb) set remotebaud 38400
> > > gdb) target remote my-server-ipaddr:port #note, the port I put
> > > here is the serial port# on the server,
> > > #not L4 port, correct?
> >
> >No, you have to use telnet port here.
>
> Hi,
>
> normally, I use the command:
> telent server-ipaddr 2001
> to access its port 1. (2002 for port 2, 2003 for port 3 ...)
>
> It looks like console server already map its L4 port into serial port.

I suppose that L4 means port 4 on the server and /dev/ttyS0 on the target
then you have to use 'target server-ipaddr 2004'.
In fact, L4 port, I mean Layer 4 (transport layer) port. Sorry for the confusion.
I am very sure I was assigned at port 1. And I use 'telnet server-ipaddr 2001'
to access the target console normally.,




If L4 means something else, then use another port.


How to debug a connection:

1. Make sure that terminal server is properly configured and the
   cable is good:  connect port 4 on the terminal server to the some known
   working target, e.g. standar UNIX serial port, do 'telnet server-ip
   2004' and type stuff on console and check responses.

2. Make sure that gdb stub is workin properly: connect port 4 on the
   terminal server to debug port on the targe, start gdb stub, again do
   'telnet server-ip 2004' and make sure that by hitting return you
   cause gdb to send you properly formed packets.

3. Start gdb and do 'target remote server-ip:2004' I would be very
   surprised if it does not work at the point.

In order to check the whole system, I did install a kgdb stub of linux on my
laptop, so that I can move it around. What I have done are:
1. enable the /dev/ttyS0 in /etc/inittab, then I can login through serial port
the check whether it works. I connect it to the port 1 of my console server,
then, I remotely login into it by 'telnet server-ipaddr 2001'. Works!
SO:
- target serial port works
- console server works
2. I move the laptop target close to my development box, and I use serial cable
to connect them directly. I start the stub on target by 'gdbstart -s 38400 -t
/dev/ttyS0'. And then start the gdb on the development box. Now I can use
gdb to debug my target box as expected.
SO:
- the stub on target is ok
- the gdb on the development box is ok
3. Now I move the laptop target back to the console server and connect the port
1 to its serial port and start the stub by 'gdbstart -s 38400 -t /dev/ttyS0', and
go the development box to start the gdb and try to access the target box by
'target remote server-ipaddr:2001'.
But it fails......

I don't know what's wrong.

Thanks
GF







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