Use the following procedures to set up your system to route IPX packets. After you complete the procedures in this section, verify that the system is routing packets properly using the procedures in "Verifying the Configuration" later in this chapter.

Configuring for Local Area Networks and Point-to-Point Links

Use this procedure to configure basic IPX routing over LAN ports and Point-to-Point Protocol (PPP) links.

Prerequisites

Before beginning this procedure, complete the following tasks:

• Log on to the system with Network Manager privilege.

• Set up the ports and paths of your bridge/router using the procedure in the Configuring Basic Ports and Paths chapter and the Configuring Advanced Ports and Paths chapter.

To configure the basic IPX router for LANs and PPP links, follow these steps:

1 .   Configure the network number connected through each router interface using:

SETDefault !<port> -IPX NETnumber = &<number>(0-FFFFFFFD) [Ethernet | Ieee | Llc | Snap | PPP]

Valid network numbers consist of up to eight hexadecimal digits in the range &0 to &FFFFFFFD. The network numbers &FFFFFFFE and &FFFFFFFF are reserved. You do not have to specify leading zeros in this network number.

You may also configure the port as unnumbered PPP. See the Configuring IP Routing chapter for more information.

2 .   Verify dynamic route learning is enabled using:

SHow !<port> -NRIP CONTrol

By default, NetWare Routing Information Protocol (NRIP) is set to Auto. If you do not enable NetWare Link Services Protocol (NLSP) as the routing protocol, Auto means both Talk and Listen. If NLSP is enabled, Auto means Talk if there are non-NLSP routers detected. The router is constantly listening.

When NRIP is listening, the router receives Routing Information Protocol (RIP) broadcasts and can maintain the routing table. When NRIP is talking, the router can send RIP broadcasts.

3 .   Enable IPX routing for each port using:

SETDefault !<port> -IPX CONTrol = ROute

4 .   If there are more users to serve than a primary server is licensed to handle and there is a backup server available, specify a preferred backup server using:

ADD !<port> -SAP PreferredServer "<server name>", ["<server name>"...]

After a list of preferred servers is configured, the IPX router responds to "get nearest server" requests with one of the reachable preferred servers regardless of the server location or number of hops. If no preferred server is available, the normal selection process of the nearest server takes place. In this way, the primary server and backup server can alternately serve all the users and lessen the burden on the primary server.

NetWare 4.0 clients and pre-4.0 clients specify different service types in their "get nearest server" requests. Pre-4.0 clients use File Server type (0x0004) while 4.0 clients are looking for Directory Name Server type (0x026B); appropriate preferred servers must be added.

5 .   Verify the IPX configuration by entering:

SHow -IPX CONFiguration

The router displays the IPX configuration information. If the -IPX CONTrol parameter is not set to ROute, if the network numbers are incorrect, or if the -NRIP and -SAP CONTrol parameters are not set to Talk and Listen for each port you are configuring, repeat steps 2, 3, and 4. Additional verification steps are provided in "Verifying the Configuration" later in this chapter.

To complete the configuration for PPP links, see the Configuring Wide Area Networking Using PPP chapter.

For LAN interfaces, IPX allows one physical network to be segmented into different logical networks, or secondary networks, and configured with different header formats. The header formats correspond to different encapsulation methods that allow the IPX protocol to deliver IPX packets. Table 55 lists the header formats supported by IPX encapsulation and the values associated with these formats.

Table 55 IPX Packet Header Formats

Values	Header Formats Supported under IPX Encapsulation
Ieee	IPX packets are encapsulated in IEEE 802.3 header format (Ethernet and FDDI).
Ethernet	IPX packets are encapsulated in Ethernet V2 header format (Ethernet only).
Snap	IPX packets are encapsulated in SNAP header format.
Llc	IPX packets are encapsulated in IEEE 802.2 header format.

3Com recommends using Ethernet V2 for Ethernet and SNAP for FDDI and token ring.

The number of secondary networks differs between interface types:

• For Ethernet interfaces, four different networks can be configured: Ethernet V2 headers (identified as Ethernet_II on Novell servers); IEEE headers (802.3 raw), identified as Ethernet_802.3 on Novell servers, and the default for Ethernet; Logical Link Control (LLC) headers (identified as Ethernet_802.2 on Novell servers); and SubNetwork Access Protocol (SNAP), identified as Ethernet_SNAP on Novell servers.

• For token ring, three different networks can be configured: LLC, SNAP, and IEEE.

• For the Fiber Distributed Data Interface (FDDI), three different networks can be configured: LLC, SNAP, and IEEE.

  For each of the interface types, configure the primary network with the SETDefault command; configure the secondary networks with the ADD command.

Figure 181 shows a router with three LAN ports of different types:

• Port 1 (Ethernet) is connected to network 100 with IEEE header format, network 200 with Ethernet header format, network 300 with LLC header format, and network 400 with SNAP header format.

• Port 2 (token ring) is connected to two networks: network 500 with LLC header format and network 600 with SNAP header format.

• Port 3 (FDDI) is connected to two networks: network 700 with SNAP header format and network 800 with LLC header format.

Figure 181 Configuring Multiple Networks for Different Header Formats

To configure the primary and secondary network for port 1 shown in Figure 181, follow these steps:

1 .   Configure the primary network for port 1 by entering:

SETDefault !1 -IPX NETnumber = 100 Ieee

The primary networks for ports 2 and 3 are configured using the SETDefault command, the appropriate port number, and the appropriate header format specifier (LLC for network 500 on port 2 and SNAP for network 700 on port 3).

2 .   Configure the Ethernet secondary network for port 1 by entering:

ADD !1 -IPX NETnumber = 200 Ethernet

The remaining secondary networks for port 1 are configured using the ADD command, the port specifier !1, and the appropriate header format specifier (LLC for network 300 and SNAP for network 400).

The remaining secondary networks for ports 2 and 3 are configured using the ADD command, the appropriate port number, and the appropriate header format specifier (SNAP for network 600 on port 2 and LLC for network 800 on port 3).

Routing IPX over Frame Relay, Asynchronous Transfer Mode data exchange interface (ATM DXI), X.25, and ATM is supported over fully meshed, partially meshed, and nonmeshed topologies.

If you plan to route IPX over Frame Relay, ATM DXI, X.25, or ATM in a partially meshed or nonmeshed topology, you must be sure that the next-hop split horizon feature is enabled by configuring neighbors. For complete information on configuring IPX routing over Frame Relay, ATM DXI, X.25, or ATM, including a discussion on fully meshed, partially meshed, and nonmeshed topologies and next-hop split horizon, see the Configuring Wide Area Networking Using Frame Relay chapter, the Configuring Wide Area Networking Using the ATM DXI chapter, the Configuring Wide Area Networking Using X.25 chapter, or the Configuring Internetworking Using ATM chapter.

Routing IPX over SMDS is supported over fully meshed and hierarchical partially meshed topologies (where virtual ports are configured to attach to distinct groups of fully meshed devices). To configure your IPX router to perform routing over SMDS, see the Configuring Wide Area Networking Using SMDS chapter. Nonmeshed topology may be used with virtual ports. To configure IPX routing over PPP, see the Configuring Wide Area Networking Using PPP chapter.

For WAN interfaces, you do not need to specify a header format. The formats are as follows:

• PPP uses the PPP header format.

• X.25 uses the X.25 header format.

• SMDS uses the SMDS header format.

• Frame Relay uses the Frame Relay header format.

• ATM uses the ATM header format.

You can assign secondary networks on WAN interfaces, but the status of those networks will be down.

Configuring IPXWAN over PPP

Novell has published a specification for IPX communications over wide area network services (such as PPP, X.25, Frame Relay) called IPXWAN. The specification outlines how IPX negotiations take place in these environments; for example, Novell IPX uses IPXWAN to exchange necessary router-to-router information before exchanging IPX NRIP, Service Advertising Protocol (SAP), and NLSP information over various WAN links. The 3Com implementation of the IPXWAN Protocol currently supports PPP, Frame Relay, and X.25.

To achieve interoperability between a 3Com bridge/router and a Novell Multi-Protocol Router (MPR) across a WAN link, you must configure IPXWAN over PPP on your bridge/router as shown in Figure 182.

If you are using the nonperiodic mode of NRIP and SAP, both sides of the WAN link must be configured the same way.

Figure 182 IPXWAN over PPP Using NRIP and SAP

Prerequisites

Before beginning this procedure, perform the following steps:

• Configure IPX routing on the LAN ports as described in "Configuring for Local Area Networks and Point-to-Point Links" earlier in this chapter.

• Configure PPP over the port as described in the Configuring Wide Area Networking Using PPP chapter.

To configure IPXWAN over PPP, follow these steps:

1 .   Configure the network numbers on the wide area interfaces that will be running IPXWAN using:

SETDefault !<port> -IPX NETnumber = &<number>(0-FFFFFFFD) [Ethernet|Ieee|Llc|Snap|X25|PPP|Frame]

Valid network numbers consist of up to eight hexadecimal digits in the range &0 to &FFFFFFFD. The network number &FFFFFFFE and &FFFFFFFF are reserved. You do not have to specify leading zeros in this network number.

2 .   Assign an internal network number to each router.

To assign the internal network number, use:

SETDefault -IPX InternalNET = &<number>(0-FFFFFFFD)

The InternalNET number must be unique throughout the IPX Internet. Valid network numbers consist of up to eight hexadecimal digits in the range &0 to &FFFFFFFD. The network number &FFFFFFFE and &FFFFFFFF are reserved.

The routers use the internal network number during IPXWAN negotiation to determine which router is the master and which router is the slave. The router with the lowest internal network number becomes the slave during link establishment and information exchange.

As shown in Figure 182, the 3Com bridge/router has the highest internal network number and is designated as the master over both Novell router #1 and #2. When packets are routed between the 3Com bridge/router and the Novell routers, the network number of the bridge/router is used. Consequently, the network numbers on port 3 and port 4 of the Novell routers do not need to be assigned.

If you assign network numbers to port 3 and port 4 of the Novell routers, the 3Com bridge/router negotiates the network numbers, and the network number of the master is used. For example in Figure 182, on port 3 of the 3Com bridge/router, network number &123 is used; on port 4 of the 3Com bridge/router, network number &131 is used during packet transmission.

3 .   For network management purposes, assign a symbolic name to each router.

The router uses this name during IPXWAN negotiation to build NRIP/SAP Information Request/Response packets. The router name must be unique throughout the IPX Internet and can be up to 48 characters in length.

To assign a symbolic name, use:

SETDefault -IPX RouterName = "<string>"

Because the IPX router does not provide a service, the router name is not advertised in SAP updates, which substantially reduces the network traffic in a large network configuration.

4 .   Determine whether to use periodic or nonperiodic (incremental) NRIP/SAP update modes on your LAN or WAN ports.

All participating routers and servers must use the same update mode to avoid stale NRIP and SAP entries and loss of network connectivity.

When used in a stable and reliable network, nonperiodic updates can eliminate the constant and expensive network traffic of IPX NRIP and SAP updates on all media, except at initialization time. After initialization, updates also are sent incrementally when changes occur.

For a LAN, use periodic updates. If two bridge/routers are connected over a WAN, use nonperiodic updates. Use periodic updates on the WAN only when mixing 3Com and non-3Com routers on the same WAN link.

To enable nonperiodic updates, use:

SETDefault !<port> -NRIP CONTrol = NoPEriodic

SETDefault !<port> -SAP CONTrol = NoPEriodic

As shown in Figure 182, Novell router #1 (port 3) and the bridge/router (port 3) are configured for nonperiodic NRIP and SAP updates. The IPX router sends out NRIP and SAP updates immediately after a LAN or WAN path comes up, which completes NRIP and SAP updates more quickly.

Set the -NRIP and -SAP CONTrol parameter to PEriodic on networks in which frequent topology changes occur.

5 .   Enable the IPXWAN protocol on the specified port of each 3Com router using:

SETDefault !<port> -IPX CONTrol = IpxWan

The NLSP provides a hierarchical structure for large IPX routing environments. NLSP uses a link-state routing algorithm that provides faster network convergence with reduced network resource overhead (bandwidth and CPU cycles) than other routing algorithms, for example, NRIP and SAP, which use a distance vector algorithm.

NLSP runs over all networking media, including LANs (Ethernet, token ring, and FDDI), and WAN/MAN (X.25, Frame Relay, ATM, SMDS, and PPP links).

Prerequisites

Before beginning this procedure, perform the following steps:

• Configure an internal network number (-IPX InternalNET parameter) to the router.

• Configure IPX network numbers on all the LAN and WAN ports.

• Enable IPX routing on those ports.

• If there are multiple logical networks on a port, make sure the primary network is configured the same for all routers on the LAN. NLSP routes communicate with each other using the primary network only.

To configure NLSP, follow these steps:

1 .   Determine and assign the area address for the router using:

ADD -NLSP AreaAddress <net> <mask>

NLSP uses a portion of the 32-bit IPX network number to identify an area. The AreaAddress parameter is used to describe the value and length of the area number. The area address is a pair of 32-bit integers expressed in hexadecimal format. The first set of numbers identified as <net> describes the value of the area number, while the second set identified as <mask> determines the length of the area address, or number of bits in the IPX network number field that are used to identify the area.

The mask is a number of leading 1 bits, followed by 0 bits. The leading 1 bits must be contiguous. Similar to the concept of IP subnet masks, the number of leading 1 bits in the mask determines the number of leading bits in the <net> field, which is considered to be the area number instead of the network number. Any bit position identified by a 0 in the mask is considered to be the network number. The following example shows the syntax of the area and mask:

ADD -NLSP AreaAddress 12345600 FFFFFF00

The mask of FFFFFF00 indicates that the first 6 characters (24 bits) in the <net> field are considered to be the area number; the last two characters (8 bits) are used to identify a network within that area. The network number is defined using the -IPX NETnumber parameter.

All network numbers assigned to routers within an area must fall within a configured area prefix. In this example, any router within the area identified as AreaAddress 12345600 FFFFFF00 must be assigned network numbers beginning with the prefix 123456XX. The valid range for network numbers within this area is 12345600-123456FF.

An area address must meet the following requirements:

• A mask is required, identifying a range of networks residing within the area.

• For example, all network numbers in the range 12345600 to 123456FF reside within the area 12345600 to FFFFFF00. It is not necessary that all of the area network numbers are addressed and operational.

• All network numbers within the area must fall within the address range.

• With an area address of 12345600 FFFFFF00, all IPX networks must begin with 123456XX. The area address 00000000 00000000 is the default and this area address includes all IPX network numbers.

2 .   Determine which interfaces to enable for NLSP.

NLSP routing should be enabled on all ports, including ports that have no NLSP routers connected to them. When NLSP is enabled on a port, and if there are other NRIP and SAP routers on the same port, NLSP automatically imports the NRIP and SAP information into the NLSP domain. NLSP automatically exports NLSP learned information to NRIP and SAP routers. The importing and exporting of information allows smooth operation between NLSP and non-NLSP routers.

If NLSP is disabled on the port, the import and export of NRIP and SAP routing information does not occur and causes network segmentation.

If you set the -NRIP and -SAP CONTrol parameters to Auto, the NLSP router determines if NRIP and SAP need to be enabled on the port. When the router detects a non-NLSP router or file server, it enables both NRIP and SAP to communicate with them; otherwise, it disables NRIP and SAP to conserve bandwidth.

If NLSP is disabled, the Auto setting for -NRIP and -SAP CONTrol means that both protocols are talking and listening. NRIP and SAP updates are continuously sent out. To disable these updates, use the NoTalk and/or NoListen values to override the Auto value.

By disabling NRIP and SAP, you conserve network bandwidth which is useful over Frame Relay or PPP lines. If Auto is selected for NRIP and SAP and all routers on the network support NLSP, and NLSP is enabled, the RIP/SAP traffic will automatically disappear from the network (except where files servers are present).

Enable the NLSP protocol on the specified port of each 3Com router using:

SETDefault !<port> -NLSP CONTrol = Enable

3 .   Display the configuration information for all ports by entering:

SHow -NLSP CONFiguration

4 .   Display the NLSP adjacencies by entering:

SHow -NLSP ADJacencies