RE: How do I cantrol the source interface

Thanks Rob,

To make things work I removed the default route and re-added specifying a
preferred interface.

ADDTCPRTE RTEDEST('*DFTROUTE') SUBNETMASK('*NONE') TOS(*NORMAL)
NEXTHOP('192.168.0.253') BINDIFC(192.168.0.3)

While this has solved the problem it is an all or nothing as you can have
only one default route.

So if you have multiple interfaces and you do not specify a binding
interface on the route a batch job presumable picks the first interface
and you have no control over this.

While natting at the firewall / outside router is an option we do not have
access to this currently and would not be my first preference.

And with Rob's RFE rejected, quite likely because too few would fall into
this requirement I believe we are stuck with forcing all default route
traffic to be bound to this hard coded interface.

Thanks

Don



From: "Rob Berendt" <rob@xxxxxxxxx>
To: "Midrange Systems Technical Discussion"
<midrange-l@xxxxxxxxxxxxxxxxxx>
Date: 06/04/2021 09:34 PM
Subject: RE: How do I cantrol the source interface
Sent by: "MIDRANGE-L" <midrange-l-bounces@xxxxxxxxxxxxxxxxxx>



Ok, the search term you are looking for is "bind specific". Often that is
controlled by individual application. They may have a config type file.
The problem is often that many IBM functions only allow you to set up bind
specific on hosting applications. For example, you can bind a specific
website to a particular IP address. Client application are a lot tougher
to bind specific. For example, saying that all your telnet sessions from
your IBM i to another location should bind to a specific address is a lot
tougher. I submitted a RFE on giving us the ability to bind specific all
such applications was rejected.

If you do not care about the application but you want all communication to
a particular address, or range of addresses, to bind from a specific
address that is doable. We have H/A software. Formerly Mimix but now
Quick-EDD. We have certain lines, VLAN and IP addresses for it to use.
CFGTCP
2. Work with TCP/IP routes
Route Subnet Next Preferred
Destination Mask Hop Interface
*DFTROUTE *NONE 10.10.6.1 *NONE
10.27.252.0 255.255.254.0 10.10.252.1 10.10.252.191

The alternative is to tell your firewall people to punch through both of
your IP addresses. We did that for our network guy who tried to set it up
so that only certain things could communicate to barcode scanners and
barcode printers. Every time we added another interface to our IBM i we
had to tell him to allow that IP address to connect to such devices too. I
probably could have set up routing to handle those. Especially since they
were all on their own subnet.

Rob Berendt