[Gllug] Recovering ISOs from a FUBARed HDD

John Edwards john at cornerstonelinux.co.uk
Wed Jun 15 15:25:10 UTC 2005

On Wed, Jun 15, 2005 at 03:09:46PM +0100, Pete Ryland wrote:
> On Mon, Jun 13, 2005 at 06:09:55PM +0100, John Edwards wrote:
>> If it's a trusted network then you could use netcat to pull it across.
>> The current Debian Sarge CD has nc symlinked to busybox.
>> On the machine with the files:
>> 	nc -l -p 12345 -c "cat file"
>> On another machine:
>> 	nc machine1 12345 > file
>> Netcat on the first machine will quit after finishing the cat and 
>> closing the connection.
>> It's not secure or 100% reliable, but can get you out of a jam when 
>> you don't have SSH available. Check md5sum or file sizes afterwards 
>> would be recommended.
> There's no reason it shouldn't be reliable.

I was thinking that there is no way to check that you are connecting 
to the correct machine, getting the correct file, that the start and 
end points are correct, or any attempt at bandwidth control. Unless 
I have misunderstood netcat, the only type of checking or control is 
what you get in TCP.

Also if anything else connects to that port on the sending machine 
(eg a portscan) then netcat will starting sending to the connection 
instead, and you have to go back and start it up again.

Most of the time it'll work, but in terms of reliability it's well 
below SSH, and probably any other TCP protocol else well. 

Any votes for least reliable network protocol ?

> BTW, one can also pipe tar or anything to netcat in the same way.

Yes that's rather useful, but just a little more difficult as 
you would need to have a read of the netcat documentation first.

I seem to remember the best way was to setup netcat to listen on 
the receiving machine, then to tar and use netcat to send to it 
from the machine with the files to the receiving machine.

|    John Edwards   Email: john at cornerstonelinux.co.uk    |
|                                                         |
| A. Because it breaks the logical sequence of discussion |
| Q. Why is top posting bad ?                             |
Gllug mailing list  -  Gllug at gllug.org.uk

More information about the GLLUG mailing list