Graphically Setting Up TCP/IP Host Routes With System i Navigator
March 19, 2014 Hey, Joe
I read your article on setting up IBM i TCP/IP host routes. But the article only contained green screen commands for host routing. Is there a way to graphically set up IBM i routes?
You can graphically work with TCP/IP Host Routes by using the System i Navigator program that comes with IBM i Access for Windows (OpsNav).
To get to a partition’s host routes for IPv4 configurations in OpsNav, open the Network→TCP/IP Configuration→IPv4→Routes node under your target partition. To work with a partition’s IPv6 host routes, open the Network→TCP/IP Configuration→IPv6→Routes node. Your OpsNav tree will look something like this when you start working with your routing table.
The right-hand pane will contain all the TCP/IP routes defined for your system. For this example, I’m using the System i Navigator program that comes with IBM i Access for Windows 7.1. You screens and options may vary, depending on what OpsNav version you are using.
To add a route to your system, right click on the Routes entry in your OpsNav tree, and select New Route from the pop-up menu that appears. A new route wizard screen will appear. The New IPv4 Route wizard screen will look something like this.
Click the Next button and a screen will appear asking you whether the new route will be bound to an existing interface (specified as the binding interface here, but also known on the green screen as the preferred binding interface or preferred interface). You can choose an existing interface that will be used for routing traffic whenever this route is selected. If you don’t choose a binding interface, the new route will be bound to a random IP interface on your machine that is able to route traffic to the routing entry’s next hop. It’s wiser to select a binding interface yourself rather than have the machine choose one for you.
After you make your binding interface selection for a new route, the New IPv4 Route wizard will take you to the Attributes screen where you can specify whether the route is a default route (the route that is used when the IP destination address doesn’t explicitly match any other routing entry), a network route (where traffic is routed for an overall network or subnet, rather than for a specific address), or a host route (where traffic is routed for a specific IP address).
Depending on which type of route you are creating (default, network, or host), the wizard will ask you to define the following items to complete your new route.
After you are finished entering valid data for your new route, click on the Finish button to add it to your partition’s existing routes.
Changing And Deleting A Route
To change or delete a route, highlight and right-click on the route you want to modify. Two options will show up on the pop-up menu that appears.
1. Delete–Remove the route from the partition.
2. Properties–Change some but not all of the route’s properties. Choosing this option will show a Properties panel with a General and an Advanced tab. You won’t be able to change the items under the General tab (route type, destination address, subnet mask, and next hop address). So if you need to change any of those values, you’ll have to delete and re-enter the route. But you can change a number of route properties under the Advanced tab for a specific route (as shown below), including the preferred binding interface, the route precedence (what 0-9 priority this route should take when there are other routes specified with the same destination address and subnet), the maximum transmission unit, and type of service:
When you are finished changing the route, click the OK button.
Two Other Differences Between The Green Screen And OpsNav For Working With TCP/IP Routes
One big difference when using OpsNav versus using the green screen is the way routing table entries are displayed. On the green screen Work with TCP/IP Routes display, the routing table is sorted and displayed by default routes first (*DFTROUTE), network routes second, and host routes third. When you work with the route list through OpsNav, the routing table is displayed by host routes first, then network routes, and finally default routes. The sequence is reversed. The OpsNav list provides a better view of how the system will transmit traffic according to its routing table.
The other difference is that OpsNav may show one system-generated 220.127.116.11 destination address route for each non-default TCP/IP route on your partition. The 18.104.22.168 route entries have a subnet mask of 240.0.0.0 and they also have preferred binding interface, route precedence, maximum transmission unit, and type of service values equal to the TCP/IP route they are mirroring.
These 22.214.171.124 routes do not show up in the green screen Work with TCP/IP routes screen. They only appear in OpsNav and in my research, it’s unclear what they are used for. So I don’t recommend trying to delete them, since they are system-generated.
If any alert reader knows what the 126.96.36.199 routing entries are used for, please feel free to email me an explanation. I may use your information in a future column.
Joe Hertvik is an IBM i subject matter expert (SME) and the owner of Hertvik Business Services, a service company that provides written marketing content and presentation services for the computer industry, including white papers, case studies, and other marketing material. Email Joe for a free quote for any upcoming projects. He also runs a data center for two companies outside Chicago, featuring multiple IBM i ERP systems. Joe is a contributing editor for IT Jungle and has written the Admin Alert column since 2002. Check out his blog where he features practical information for tech users at joehertvik.com.