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Community Member

Apply IPX network to subinterface ?

I am trying to apply ipx network numbers to subintefaces and keep getting the following message.

"Encapsulation already in use by IPX network A, on interface Ethernet0.1"

I am using ios 12.0(26)

Cisco Employee

Re: Apply IPX network to subinterface ?

You cannot have IPX encapsulations under a sub-interface.

Community Member

Re: Apply IPX network to subinterface ?

According to the documnetaTION ON THE cISCO SITE about novell you can have it under subinterfaces. Infact I used it under subs before and it worked


Re: Apply IPX network to subinterface ?

Sounds like maybe you're trying to load another IPX network number on that subinterface with the same Novell IPX frame type or LAN encapsulation, and the router won't let you. I assume you are trying to do interVLAN routing over some sort of VLAN trunk connection (802.1Q or ISL), and each of the VLANs has multiple IPX frame types on it. Are you looking to do something like this?

interface Ethernet0.1

encapsulation dot1q 1

ipx network A encapsulation sap

ipx network A8023 encapsulation novell-ether secondary

ipx network A11 encapsulation arpa secondary

ipx network AA encapsulation snap secondary

interface Ethernet0.2

encapsulation dot1q 2

ipx network B encapsulation sap

ipx network B8023 encapsulation novell-ether secondary

ipx network B11 encapsulation arpa secondary

ipx network BB encapsulation snap secondary

The encapsulation with "dot1q" refers to the VLAN number. The encapsulations with "sap", "novell-ether", "arpa", or "snap" refer to IPX frame types on that VLAN. If you're loading support for multiple frame types, you need to use the "secondary" option on anything you enter after the first one.

My guess is, you were trying to load multiple frame type support on the subinterface by entering several "IPX network xxx" commands, but were not specifying the LAN encapsulations. So the router kept using the Cisco default, "novell-ether" (Novell's ETHERNET_8023 frame type) and wouldn't let you do it. The "secondary" option would not help here, either. You cannot have two different IPX network numbers with the same frame type on the same LAN.

FYI, Novell's default frame type these days is ETHERNET_8022, which Cisco calls "sap"; this can lead to confusion, if you depend on the defaults matching up. The others are ETHERNET_II and ETHERNET_SNAP, which Cisco calls "arpa" and "snap", respectively.

What kind of router are you using?

Community Member

Re: Apply IPX network to subinterface ?

I am in need of only novell-ethernet on multiple vlans. What I am trying to do is the following.

int e0.1

ipx network A encap novell-ethernet

int e0.2

ipx network B encap novell-ethernet

To give you a cull scenario. I took over a network and installed my own equipment and was told that IPX was not needed. i put a 3550 switch in place of a router to take care of the inter-vlan routing. After the fact I found out that they do need ipx and the 3550 does not handle this. So i put a router on the network just to do IPX.

Any help you can offer would be greatly apprciated.




Re: Apply IPX network to subinterface ?

Does your router only have one LAN interface? And what model is it?

From my personal experience, I know Cisco used to require "Plus" versions of the IOS to support interVLAN IP routing with subinterfaces on the 2600 series. Not sure if this is still true; maybe you need IP/IPX Plus, or Desktop Plus to do it with IPX too.

If your router has only one interface, and assuming you have the right IOS, then you need to configure a VLAN trunk port (802.1Q or ISL) on the switch, connect your router to it, and configure VLAN encapsulations on your router's subinterfaces.

Your example above does not show any VLAN encapsulations under the subinterfaces. Without them, maybe the router thinks you're trying to put two IPX network numbers on the same interface with the same frame type, which violates Novell IPX networking rules.

If you're out of luck with the Cisco equipment, and it's a true Novell shop (that is, you have at least one Novell server), a quick-and-dirty solution could be to put a second NIC in the server, patch it into the other VLAN, and configure the server to route IPX.

Hope this helps.

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