[PLUG] Needed: Modern equivalent of a "null-modem cable"

Russell Senior russell at personaltelco.net
Sun Jan 15 04:33:50 UTC 2017


>>>>> "Richard" == Richard Owlett <rowlett at cloud85.net> writes:

Richard> I suspect what I'm looking for is ONE 3 ft piece of terminated
Richard> Cat6 cable ;) I have two laptops - one (a Lenovo T43) speaks
Richard> only WinXP Pro, the other (a Lenovo T430) only Debian Jessie.

You do *not* need a crossover cable.  The T430 *certainly* (as in no
doubt whatsoever) does auto-discovery of rx and tx.

You will, however, need non-colliding IP addresses before TCP or UDP
connections between the two computers will work.

Most distributions will come with ethernet expecting dynamic
configuration using DHCP. This is typically provided using a wireless
router or some-such device.  Since you reject that solution, the most
direct thing to do is to assign static IP addresses using whatever
mechanism is well adapted to your distribution.  On debian, this is
probably /etc/network/interfaces.



The addresses should be something like 192.168.1.n/24 and
192.168.1.m/24, respectively, where n and m are positive integers, n
is not equal to m, and n<255 and m<255.  The netmask for a /24 network
is 255.255.255.0.

The /etc/network/interfaces stanza would look like this:

auto eth0
iface eth0 inet static
        address 192.168.1.2
        netmask 255.255.255.0
        network 192.168.1.0
        broadcast 192.168.1.255

where in this case n = 2.  Then, say: "ifup eth0" and then check the
configuration with "ip a" or "ifconfig -a".

Good luck!


-- 
Russell Senior, President
russell at personaltelco.net



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