Re: Null modem connection

[Jim McCloskey <mcclosk@ling.ucsc.edu>]

Andreas Nolda <nolda@nolda.dialup.fu-berlin.de> wrote:

  |> how can I connect two Debian machines by a null modem cable so
  |> that I can point Dselect on one of them (with only the base
  |> system installed) to the other (with access to a Debian CD-ROM)
  |> using the FTP or the NFS access methods?
  |> 
  |> Andreas Nolda

Andreas:

Oddly enough, I did exactly this today. I have a laptop that has no
CD-ROM drive and whose only net connection is via PPP (too slow to use
the FTP access method for dselect). I installed the base system for
2.0 on the laptop using floppies. Then I set up a PLIP connection
between the parallel port of the laptop and the parallel port of my
desktop machine---which does have a CD-ROM drive. Once the PLIP
connection was up, I was able to turn the desktop machine into an NFS
fileserver for the laptop. I mounted the Debian 2.0 CD at \mnt on the
desktop machine, and then mounted it via the NFS link on the laptop,
and installed 2.0. It all went very smoothly, as far as I can tell so
far anyway.

To set up the PLIP connection, I recommend that you look at the
PLIP-Mini-HOWTO written by Andrea Controzzi. The latest version is
available at his web-page: http://www.cli.di.unipi.it/~controzz .
It's very clear and complete. 

Setting up the NFS connection is easy after that:

On the server:

[1] Start the relevant daemons:

               /usr/sbin/rpc.portmap (should already be running)
               /usr/sbin/rpc.mountd
               /usr/sbin/rpc.nfsd

    This assumes that you have NFS support built into your kernel.

[2] Make sure that the file /etc/exports exists and that it contains
    the appropriate entry:

        /mnt    lapdog
          ^       ^
          |       |
                name of client machine
          |
      the directory on the server that is to be exported

[3] If any changes were made to /etc/exports, make the relevant
    daemons re-read the file with:

             killall -HUP rpc.nfsd rpc.mountd


				 ---
On the client machine:


[4] Create a directory (if it doesn't already exist) to be the
    mountpoint for the file-system on the server, say /nfs.

[5] Mount the remote filesystem with:

             mount -t nfs SERVERNAME:/mnt /nfs

[6] *Very important*  Make sure to unmount before shutting down:

             umount /nfs

If you've mounted a CD-ROM on \mnt on the server, you then have full
access to the contents of the CD-ROM from the client machine, and you
can use the `mounted' access method in dselect.

Hope this helps,

Jim