[CentOS] Re: usb to usb comm ports - possible? how?

Les Mikesell lesmikesell at gmail.com
Wed Jul 30 21:40:06 UTC 2008

James B. Byrne wrote:
> On Wed, July 30, 2008 15:14, James B. Byrne wrote:
>>> I have an i686 mono core system configured as a CentOS-5.2 server.
>>> It has one DB9P RS-232 serial connector and six USB connectors.
>>> The DB9p is configured as STTY0 for the attached MultiTec MT5638ZBA
>>> fax modem.  I would very much like to connect my MS WindowsXPpro
>>> laptop, which only has USB connectors, to this server via telnet
>>> or ssh over a direct connection.
> On Wed Jul 30 20:19:44 UTC 2008, Les Mikesell lesmikesell at gmail.com wrote:
>> I can't imagine why anyone would want to do this on any system
>> capable of using a network connection instead.
> The availability of the nic cannot be guaranteed since the machine is
> being configured on one netblock and then being physically transferred to
> a distant location. It is entirely possible that whatever IP address is
> assigned to the eth0 connection here as being the one that will be used
> there may not actually work on the target network.  The purpose of the
> serial connection is to permit a laptop to substitute for a
> monitor/kb/mouse on site in that eventuality.  If it proves too cumbersome
> to enable direct host to host communications via usb then we will simply
> ship a 15" flat screen, kb and mouse with the unit and have them returned
> afterwards.

If you are confident that the server itself would be up and functional, 
you could configure an extra NIC with a private subnet that offers DHCP 
so a laptop plugged in with a crossover cable would be able to connect 
to a known address.  It might even be possible to make that happen after 
a USB adapter is plugged in.

> We could, I suppose, reconfigure the available serial port as a tty and
> then connect that way, establish network connectivity, detach, and
> reconfigure the DB9p as an STTY for the fax service.

Can't you just run one of the getty's that know how to start both fax 
and data services on the fax modem and either swap cables or dial it up 
if you need to log in on the serial port?  I thought both hylafax and 
sendfax/vgetty could do that.

   Les Mikesell
    lesmikesell at gmail.com

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