Re: TCP/IP and Components

[Chuck Morehead <cbmorehead@xxxxxxxxxx>]

<snip>
> First:    What are the functions of  ROUTES, *DFTROUTE, NEXTHOP, and
PREFERRED INTERFACE and why are they needed.
Different subnets don't normally "talk" to each other.  If you want them to,
then you need to tell them how to get to each other, i.e. what "route" to
take.  E.g. to get from a machine with IP 10.1.1.15 (assuming mask of
255.255.255.0) to subnet 10.1.2.0, you need to tell the 10.1.1.15 system
where the router is, e.g. perhaps it is 10.1.2.1.  This tells the 10.1.1.15
machine to go to 10.1.2.1 for any 10.1.2.0 address.

The *DFTROUTE option is the default route - it is tried if there are no
specific routes that meet the request.  It is the same as a "default
gateway" in Windows.

>
> Second:    How should TCP/IP domain be setup and what are the relationship
and requirements between HOST NAME, DOMAIN NAME, DOMAIN
>                 NAME ADDRESSES as they apply to AS/400 TCP/IP domain.
This is a matter of opinion, and is very arbitrary if you are working with
an internal network.  E.g. use "yourcompanyname.com" for the domain name,
and your AS/400's name for the host name.  E.g. here our domain is
NOKUSE.COM.  (In our situation we use the same domain as our public domain,
which does not cause us problems since we do not host our own Internet
servers in-house.  If you do have Internet servers in-house then you may
want a different domain name for internal systems.  Again, this is very
arbitrary.)  Then if our AS/400's host name was AS400 the qualified name
would be AS400.NOKUSE.COM.

As for IP address, choose a private IP scheme, e.g. 192.168.20.0 or
10.1.1.0.  Generally servers (i.e. anything that requires a static IP) use
the first 10 (or more if you need them) IP's.  So your router may be
10.1.1.1, your AS/400 may be 10.1.1.2, you may have 3 print servers using
10.1.1.3-5, etc.  This allows you to set your DHCP server (if you choose to
use one) to exclude that range.

> Third:    What are the functions of a *LOOPBACK address.
Loopback is for testing TCP/IP locally to make sure you at least have TCP/IP
up and running.  It does not test outside the machine you are working on.
>
<snip>

There is a lot more to all of this, but basic configuration on the AS/400 is
easy.  Configuring and securing it - especially if your network is connected
to the Internet - is another animal.

Chuck