Ethernet Routing Switch 8600/8800 - Avaya

Ethernet Routing Switch

8600/8800

Engineering

> OSPF Technical Configuration Guide

Avaya Data Solutions

Document Date: November 2010

Document Number: NN48500-602

Document Version: 1.4

ERS 8600 / 8800 OSPF Technical Configuration Guide 2

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November 2010

© 2010 Avaya Inc. All Rights Reserved.

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Abstract This document provides examples on configuring OSPF on the Ethernet Routing Switch 8600.

Note: Configuration steps shown in this document are also included in the Release 3.5 Technical Publication "Configuring IP Operations".

Revision Control

No Date Version Revised By Remarks

1 14/05/2003 1.0 J. Vant Erve Initial Draft

2 11/06/2003 1.1 R. Lapuh Updated Sections 5 and 7

3 08/14/2003 1.2 J. Vant Erve Added Addendum A - CLI

4 02/02/2004 1.3 J. Vant Erve Added OSPF timers and Route Summarization

5 12/22/2010 1.4 K. Marshall Rebranded Avaya


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Table of Contents Figures .......................................................................................................................................................... 6

Tables ............................................................................................................................................................ 7

1. OSPF Overview .................................................................................................................................... 9

2. Circuitless IP (CLIP) .............................................................................................................................. 9

3. Configuring OSPF ............................................................................................................................... 10

4. OSPF Network Types ......................................................................................................................... 11

5. Equal Cost Multi Path (ECMP) ............................................................................................................ 12

6. Security ............................................................................................................................................... 14

6.1 Simple Password Mechanism ..................................................................................................... 14

6.2 Message Digest 5 (MD5) ............................................................................................................ 14

6.3 Configuration Example – Using MD5 .......................................................................................... 15

7. OSPF Neighbor States ....................................................................................................................... 16

8. OSPF Areas ........................................................................................................................................ 18

8.1 Classification of Routers ............................................................................................................. 18

8.2 Types of OSPF Areas ................................................................................................................. 19

9. Configuration Examples ...................................................................................................................... 27

9.1 OSPF Route Distribution to RIP, RIP to OSPF (AS-external-LSA Type 1 Metrics) .................... 27

9.2 Distributing an Internet Default Route to OSPF using AS-external-LSA Type 2 ........................ 30

9.3 Controlling External Routes Advertised in an NSSA Area .......................................................... 32

9.4 Route Summarization between Area‟s ........................................................................................ 37

9.5 Adjusting OSPF Timers ............................................................................................................... 37

9.6 Complex Configuration Example:................................................................................................ 38

10. Appendix ......................................................................................................................................... 45

10.1 Circuitless IP (CLIP) CLI ............................................................................................................. 45

10.2 OSPF Brouter Port CLI ............................................................................................................... 45

10.3 OSPF Network CLI ...................................................................................................................... 45

10.4 MD5 Authentication CLI .............................................................................................................. 46

10.5 Add OSPF Interface to New Area CLI ........................................................................................ 46

10.6 Stub Area CLI .............................................................................................................................. 46

10.7 NNSA ASBR Router CLI ............................................................................................................. 47

10.8 OSPF ASBR CLI ......................................................................................................................... 48

10.9 Default Route to OSPF CLI ......................................................................................................... 49

10.10 Controlling External Routes (NSSA Area) CLI ........................................................................ 50

11. Software Baseline ........................................................................................................................... 52


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12. Reference Documentation .............................................................................................................. 52


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Figures

Figure 1: OSPF Configuration ..................................................................................................................... 10

Figure 2: OSPF Network Type .................................................................................................................... 11

Figure 3: Equal Cost Multi Path (ECMP) .................................................................................................... 12

Figure 4: MD5 Authentication ..................................................................................................................... 15

Figure 5: Normal Areas ............................................................................................................................... 20

Figure 6: ABR Configuration Example ........................................................................................................ 21

Figure 7: Stub Area Example ...................................................................................................................... 23

Figure 8: NSSA ........................................................................................................................................... 25

Figure 9: NSSA Configuration Example ...................................................................................................... 25

Figure 10: OSPF ASBR Configuration Example ......................................................................................... 27

Figure 11: Distributing Default Route to OSPF ........................................................................................... 30

Figure 12: Controlling External Routes (NSSA Area) ................................................................................. 32

Figure 14: PP8600 Network Example ......................................................................................................... 38


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Tables


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Conventions This section describes the text, image, and command conventions used in this document.

Symbols

Tip – Highlights a configuration or technical tip.

Note – Highlights important information to the reader.

Warning – Highlights important information about an action that may result in equipment damage, configuration or data loss.

Text

Bold text indicates emphasis.

Italic text in a Courier New font indicates text the user must enter or select in a menu item, button or command:

ERS5520-48T# show running-config

Output examples from Avaya devices are displayed in a Lucida Console font:

ERS5520-48T# show sys-info

Operation Mode: Switch

MAC Address: 00-12-83-93-B0-00

PoE Module FW: 6370.4

Reset Count: 83

Last Reset Type: Management Factory Reset

Power Status: Primary Power

Autotopology: Enabled

Pluggable Port 45: None




Base Unit Selection: Non-base unit using rear-panel switch

sysDescr: Ethernet Routing Switch 5520-48T-PWR

HW:02 FW:6.0.0.10 SW:v6.2.0.009

Mfg Date:12042004 HW Dev:H/W rev.02


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1. OSPF Overview

Open Shortest Path First is a link state protocol designed as a standards based Internal Gateway Protocol (IGP) for the purpose of interconnecting users and networks. OSPF maintains a link state database of interface, link, router, and network status in order to calculate the shortest path to each and every network element. From the link state database, a routing table is built. This calculation is based on Dijkstra‟s model of calculating the shortest path from one point to another.

OSPF Standards supported on Ethernet Routing Switch 8600

The Ethernet Routing Switch 8600 supports the following standards:

RFC 1253 (OSPF MIB)

RFC 1583 (OSPF version 2)

RFC 2178 (OSPF version 2)

RFC 1850 (OSPF Management Information Base)

RFC 2178 (OSPF MD5 cryptographic authentication)

Dijkstra’s Algorithm

This calculation is used to determine the best path to any network based on the total path cost. All paths to a given network are determined and the cost calculated, however, only the best path will be used populate the routing table.

2. Circuitless IP (CLIP)

A Circuitless IP address, sometimes referred to as a loopback address, is an IP address that is not tied to any specific interface. Since it is not tied to a physical port or VLAN, its state is always active. It is highly recommended to use the Circuitless IP address for the OSPF Router-ID. By doing so, the OSPF Router-ID is always active regardless of any port state (up/down).

To configure CLIP and use it for the OSPF Router-ID, the following commands are used.

Step 1 Configure a Circuitless IP address

config ip circuitless-ip-int X create

<ipaddress/mask>

config ip circuitless-ip-int X ospf

enable

This step creates a circuitless IP address which will be used for the OSPF Router-ID where X is the CLIP ID and can be any instance from 1-32. The CLIP IP address typically uses a 32-bit mask.

Step 2 Enable OSPF

config ip ospf admin-state enable

config ip ospf router-id <CLIP IP Address>

config ip ospf enable

These commands enable OSPF and set the OSPF Router-ID using Circuitless IP created in Step 1.


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3. Configuring OSPF

OSPF can be configured at an interface (brouter port) or VLAN (port or IP-Subnet) level.

Figure 1: OSPF Configuration

In reference to the drawing below, the following configuration steps are used to configure OSPF on brouter port 2/1 and VLAN2:

Step 1 Configure OSPF Interface – brouter port

config ethernet 2/1 ip create 10.1.1.21/30

2134

config ethernet 2/1 ip ospf enable

These two commands configure port 2/1 as a brouter port with VLAN ID 2134 and enables OSPF on this interface.

Step 2 Configure OSPF Interface – VLAN

config vlan 2 create byport 1

config vlan 2 ports add 1/2

config vlan 2 ip create 172.3.1.1/24

config vlan 2 ip ospf enable

These commands create port-based VLAN 2 under STG 1 with OSPF.


config ip circuitless-ip-int 1 create

1.1.1.1/32

config ip circuitless-ip-int 1 ospf

enable

This step creates a circuitless IP address which will be used for the OSPF Router-ID

Step 4 Enable OSPF Globally

config ip ospf router-id 1.1.1.1


These commands enable OSPF and assigns the Circuitless IP created in Step 3 as the OSPF Router-ID


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4. OSPF Network Types

OSPF Network Types were created to allow OSPF neighboring between routers over different types of network infrastructures. That being the case, each interface can be configured to support each network type. The following table defines the network types and usages that the Ethernet Routing Switch 8600 supports.

Interface Type Usage

Broadcast Will automatically discover every OSPF router on the network by sending OSPF Hello‟s to the multicast group AllSPFRouters (224.0.0.5). Neighboring is automatic and need not be configured. Typically used in an Ethernet, ATM, or certain Frame Relay environments.

Non-Broadcast Multi-Access

OSPF NBMA network type was used to correctly model network environments that do not have native Layer 2 broadcast/multicast capabilities, such as Frame Relay and X.25. Hellos are unicasted to manually configured neighbors.

Passive Allows interface network to be included in OSPF without generating LSAs or forming adjacencies. Typically used on an access network, or on an interface that is used for BGP peering. This also limits the amount of CPU cycles required to process Dijkstra.

Configuring OSPF Network Type:

The OSPF Network type can be configured by using the following command:

config ethernet x/y ip ospf interface-type ({broadcast | nbma | passive}

Where:

x = slot #

y = port #

Config Example – OSPF Network Type

Figure 2: OSPF Network Type

For this example, we will configure VLAN 2 on PP8600A with OSPF and set the interface type as passive. By configuring VLAN 2 as passive, no OSPF hello messages will be sent on this segment while still advertising this interface to the rest of the OSPF network.

Step 1 Configure OSPF Interface – brouter port



These commands create a port-based VLAN 2 under STG 1 with OSPF enabled and sets the interface type as passive.


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config vlan 2 ip ospf interface-type

passive


5. Equal Cost Multi Path (ECMP)

ECMP is a feature, which will load balance routed IP traffic across up to four equal cost paths. The Ethernet Routing Switch 8600 supports ECMP operation for OSPF, RIP, static routes, and default routes. There are a few benefits of ECMP when used with OSPF:

1) no need to rerun Dijkstra should the main path fail, the other ECMP path(s) will automatically take the load.

2) loadsharing implies better use of network facilities.

The traffic distribution algorithm is identical to the Multi-Link Trunk (MLT) algorithm for IP datagrams:

MOD (DestIP(X)[5:0] XOR SrcIP(Y)[5:0],#of active links) 'XOR the last 6 bits of the source and destination IP address, divide by the number of links, and take the remainder.Configuration Example – ECMP

Figure 3: Equal Cost Multi Path (ECMP)

Configuration of ECMP is quite simple. For example, in reference to PP8600A, the commands to enable ECMP over two paths is as follows:

config ip ecmp enable

config ip ecmp-max-path 2

After ECMP is configured, ECMP paths can be verified in the routing table. Those paths with an E in the Type column are designated equal cost paths. In this example we see two routes to 1.1.1.2, and two routes to 10.1.30.0.

show ip route info


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Response from A:

Ip Route

================================================================================

DST MASK NEXT COST VLAN PORT PROT AGE TYPE PRF

--------------------------------------------------------------------------------

1.1.1.1 255.255.255.255 1.1.1.1 1 0 -/- LOC 0 DB 0

10.1.40.0 255.255.255.255 10.1.1.2 12 2190 2/7 OSPF 0 IBE 20

10.1.40.0 255.255.255.255 10.1.1.6 12 2191 2/8 OSPF 0 IBE 20

2.1.1.0 255.255.255.252 2.1.1.1 1 3999 -/- LOC 0 DB 0

10.1.1.0 255.255.255.252 10.1.1.1 1 - 2/7 LOC 0 DB 0

10.1.1.4 255.255.255.252 10.1.1.5 1 - 2/8 LOC 0 DB 0

. .

. .

10.1.30.0 255.255.255.0 10.1.1.2 11 2190 2/7 OSPF 0 IBE 20

10.1.30.0 255.255.255.0 10.1.1.6 11 2191 2/8 OSPF 0 IBE 20

13 out of 11 Total Num of Dest Networks,13 Total Num of Route Entries displayed.

--------------------------------------------------------------------------------

TYPE Legend:

I=Indirect Route, D=Direct Route, A=Alternative Route, B=Best Route, E=Ecmp Route

, U=Unresolved Route, N=Not in HW


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6. Security

The Ethernet Routing Switch 8600 implementation of OSPF includes security mechanisms to prevent the OSPF routing domain from being attacked by unauthorized routers. This prevents someone from joining an OSPF domain and advertising false information in its OSPF LSAs. Likewise, it prevents a misconfigured router from joining an OSPF domain.

Simple Password Mechanism 6.1

The Simple Password is a text simple password mechanism, only routers that contain the same authentication id in their LSA headers can communicate with each other. To configure simple password, use the following commands.

Brouter Ports:

config ethernet x/y ip ospf authentication-type simple

config ethernet x/y ip ospf authentication-key <string>

Where:

x = slot #

y = port #

VLAN:

config vlan x ip ospf authentication-type simple

config vlan x ip ospf authentication-key <string>

Where:

x = VLAN #

The problem with this feature is that the password is stored in plain text and can be read off the config file or LSA packet.

Message Digest 5 (MD5) 6.2

This is the preferred method of OSPF security as it provides standards based (RFC 1321) authentication using 128-bit encryption. It is almost impossible to compute or extrapolate the decryption codes from the OSPF packets. Basically each OSPF packet will have a message digest appended to it which needs to be matched between sending and receiving routers. The message digest is calculated on either side, based on the MD5 Key and any padding, then compared, if they do not match, the packet is rejected.

The first step is to create a MD5 key and key-id and then set the authentication type for message-digest.

config ip ospf interface <IP address> add-message-digest-key <md5-key-id> md5-

key <value>

config ip ospf interface <IP address> authentication-type message-digest

Where:

md5-key-id = 1-255

md5-key value = alphanumeric password of up to 16 bytes {string length 0..16}

auth-type = authentication type {none|simple|message-digest}


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Configuration Example – Using MD5 6.3

Figure 4: MD5 Authentication

Assuming we wish to enable MD5 authentication between PP8600A and PP8600B, the commands are as follows:

Step 1 Configure PP8600A

config ip ospf interface 10.1.1.1 add-

message-digest-key 1 md5-key qwsdf89

config ip ospf interface 10.1.1.1

authentication-type message-digest

These commands enable md5 authentication for ospf interface 10.1.1.1 using key „qwsdf89‟.

Step 2 Configure PP8600B

config ip ospf interface 10.1.1.2 add-

message-digest-key 1 md5-key qwsdf89

config ip ospf interface 10.1.1.2

authentication-type message-digest

These commands enable md5 authentication for ospf interface 10.1.1.2 using key „qwsdf89‟.


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7. OSPF Neighbor States

Upon initial startup, routers will attempt to find and form adjacencies with other OSPF routers via Hello packets. Once these are received the routers perform some handshaking before adjacency is established. The following table describes the various states of forming an adjacency.

Step State Description

1 Down This is the initial OSPF neighbor state. It means a router has not received any information (hellos) from its neighbor even if it can still send hellos to its neighbor. This state can occur for NBMA or Point-to-Multipoint neighbors. During a full adjacency state, if a router does not receive hello packets from a neighbor within the Router Dead Interval time, then the neighbor state changes from Full to Down. The default Dead Interval time is 4 x Hello Interval, which by default is 40 seconds. This state does not occur on Broadcast networks, which is initially in an Init state.

2 Attempt Also on NBMA interfaces, this state occurs when the router attempts to send unicast hellos to any configured interfaces.

3 Init Router has received a general Hello packet (without its Router ID) from another router.

4 2-Way Router received a Hello directed to it from another router. (Hello contains its Router ID).

5 ExStart Master/Slave election process.

6 Exchange Link State Database is exchanged

7 Loading Processing of the LSDB for input into the routing table. Router may request LSA for missing or corrupt routes.

8 Full Normal full adjacency state.

7.1.1 Troubleshooting Neighbor States

The following command will show all the neighbors and the current state of adjacency.

ERS-8610:6# show ip ospf neighbors

================================================================================

Ospf Neighbors

================================================================================

INTERFACE NBRROUTERID NBRIPADDR PRIO_STATE RTXQLEN PERMANENCE

------------------------------------------------------------------------------------------------------------------------

10.1.1.22 1.1.1.1 10.1.1.21 100 Full 0 Dynamic

10.1.1.17 1.1.1.5 10.1.1.18 0 Full 0 Dynamic

10.1.1.9 1.1.1.4 10.1.1.10 1 Full 0 Dynamic

Total ospf neighbors: 3


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Most problems with OSPF occur at initial startup where the router cannot form adjacencies with other routers and the state is stuck in INIT or EXSTART/EXCHANGE.

INIT State problems

A router may be stuck in INIT state and not form an adjacency. This could mean a couple things:

a) There is a mismatch in authentication keys or that both sides are not configured for authentication. By issuing the „trace Level 6 2‟ command, we can see the OSPF packets being received. The example below shows the error received when there is an authentication failure:

ERS 8600 # trace level 6 2

ERS 8600 # trace screen on

[03/24/03 15:55:07:216] tMainTask OSPF: os_recv.c : 710 : verify_ospf_packet: authType mismatch ipa= 10.1.1.18

b) The path is not reachable due to Access Lists implemented on routers, ensure the multicast address of 224.0.0.5 is able to traverse the link. If multicast traffic is being blocked for some reason, the Ethernet Routing Switch 8600 may have to be configured for OSPF NBMA instead of Broadcast.

c) When forming an adjacency over ATM link, both routers must be able to support Inverse ARP which will map the IP address to a PVC. Ethernet Routing Switch 8600 will do this automatically, however in the case that Ethernet Routing Switch is connecting to another router, ensure that Inverse ARP is enabled on the other router. If Inverse ARP is not supported then it may be necessary to configure a static ARP entry.

EXSTART/EXCHANGE Problems

Both routers may recognize each other and have moved beyond 2-way, however there may be a problem with the routers being stuck in EXSTART/EXCHANGE state. This is usually caused by a mismatch in MTU sizes, i.e. one router be set for a high MTU size and the other is default at a smaller value. Depending on the size of the LSDB, the router with the smaller value may not be able to process the larger packets and thus be stuck in EXSTART/EXCHANGE state. Ensure that the MTU sizes match! This is typical when interoperating with other vendors. Use “Trace Level 6 2” to help troubleshoot this problem.

a) Since release 3.2.2.2, the Ethernet Routing Switch 8600 starting checking for the OSPF MTU mismatch. The following is taken form the 3.2.2.2 release notes:

b) In Ethernet Routing Switch 8600 Software Release 3.2.0.0 and higher, the supported MTU size for OSPF is 1500 bytes by default. Incoming OSPF DBD packets would be dropped if their MTU size is greater than 1500 bytes.

c) To allow the Ethernet Routing Switch 8600 routing switch to accept OSPF DBD packets with a different MTU, a CLI command is introduced in Software Release 3.2.2.2, which is configurable per OSPF interface:

config ip ospf interface <ip address> mtu-ignore <enable|disable>

default value of mtu-ignore is disable)

Once "mtu-ignore" is enabled the MTU Check on the incoming OSPF DBD packet is not performed.

NOTE: This change will however still not allow the Ethernet Routing Switch 8600 routing switch to process packets sent on ATM links larger than 1950 bytes.


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8. OSPF Areas

In large networks with many routers and networks, the link state database (LSDB) and routing table can become very large. Large route tables and LSDBs consume memory. Processing of link state advertisements results in more CPU cycles being needed to make forwarding decisions. To help reduce these undesired effects, an OSPF network can be divided into sub-domains called areas. An area is made up of a number of OSPF routers with the same area identification.

By dividing a network into multiple areas, a separate LSDB consisting of router LSA‟s and network LSA‟s are maintained for each area. Each router within an area will maintain a LSDB only for the area to which it belongs. In other words, the area‟s router-LSA‟s and network-LSA‟s are not flooded beyond the area‟s borders. Hence, the impact of a topology change is localized to the area that it occurs. The only exception to this is for the area border routers, which must maintain a LSDB for each area to which they belong. Changes in topology are advertised to the rest of the network by the area border routers by advertising Summary-LSAs.

Area‟s are identified by a 32-bit Area ID and is expressed in IP address format such as 0.0.0.0 for 0. Area 0 is also known as the backbone area and is responsible for distributing routing information to all other areas. If multiple areas are used, they should all be attached to the backbone via an Area Border Router (ABR), which connects area 0.0.0.0 to the non-backbone area(s). If an area cannot be physically directly connected via an ABR to area 0, you will need to configure a Virtual Link to logically connect the area to the backbone area.

Classification of Routers 8.1

When an OSPF Autonomous System is broken up into multiple OSPF areas, the routers are further divided into specific functions:

Internal Routers

A router that has all its networks and interfaces belonging to one area. This router will have a one LSDB belonging to this area.

Area Border Routers (ABR)

An ABR router connects to two or more OSPF areas. It will have a separate LSDB for each area it is attached to. It will in turn condense the routing topology from its attached area for distribution to the OSPF backbone area. The backbone in turn will distribute this information to all other areas. ABR‟s use Summary-LSA‟s to advertise IP subnets into the backbone by using Type 3 Summary-LSAs and Type 4 ASBR-summary-LSAs. Type 4 ASBR-summary-LSAs advertises the location of the ASBRs from area to area.

Backbone Routers

A backbone router is simply a router that has an interface connected to the backbone area. This includes all routers including the ABR.

Autonomous System Boundary Router (ASBR)

An ASBR router is a router that has a connection to another Autonomous System. To distribute into OSPF any external routes that originated from a protocol such as RIP, BGP-4, IS-IS or Static Routes, the router must be configured as an ASBR. An ASBR router will import external routes into the OSPF domain by using AS-external-LSAs (LSA Type 5) originated by the ASBR. AS-external-LSAs are flooded across area borders. When an ASBR imports external routes, it may import routes info OSPF using external Type 1 or Type 2 metrics. This will give a four-level routing hierarchy as show in the table below according to routing preference.


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Level Description

1 Intra-area routing

2 Inter-area routing

3 External Type 1 metrics

4 External Type 2 metrics

This results in a routing preference from most preferred to least preferred of:

1) routing within an OSPF area

2) routing within the OSPF domain

3) routing within the OSPF domain and external routes with External Type 1 metrics

4) routing within the OSPF domain and external routes with External Type 2 metrics

For example, an ASBR can be configured to import RIP routes into OSPF with external Type 1 metrics. Another ASBR can be configured to import Internet routes and advertise a default route with an external Type 2 metric. This will result in RIP imported routes having a higher preference than the Internet imported default routes. In reality, External Type 2 metrics should always be used for BGP Internet routes whereas External Type 1 should always be used for RIP imported routes. The reason for this is routes imported into OSPF as External Type 1 are supposed to be from IGP (internal gateway protocols) whose external metric is comparable to OSPF metrics. With External Type 1 metrics, OSPF will add the internal cost to the ASBR to the external metric. External Type 2 metrics are used for EGP (exterior gateway protocols) whose metric is not comparable to OSPF metrics. For External Type 2 metrics, only the internal OSPF cost to the ASBR router is used in the routing decision.

Types of OSPF Areas 8.2

In reference to the area types below, the following chart displays the various LSA types exchanged between area‟s. LSA‟s are used to share link state information among routers; there are 7 different types. They typically contain information about the router and its neighbors and are generated periodically to ensure connectivity or generated upon the change in state of a router/link (up/down).

LSA Type Description Area of Distribution

1 LSA Type 1 are called router-LSAs and is originated by a router to describe its set of active interfaces and neighbors.

Only within the same area.

2 LSA Type 2 are called network-LSAs and describes a network segment such as broadcast or NBMA. In a broadcast network, network-LSAs are originated by the Designated

Router (DR).

Only within the same area.

3 LSA Type 3 are called network-summary-LSAs. Describes the networks within an area. Originated by the Area Border Router (ABR).

Passed between areas.


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LSA Type Description Area of Distribution

4 LSA Type 4 are called ASBR-summary-LSAs and advertises the location of the ASBRs from area to area


5 LSA Type 5 are called AS-external-LSAs. Describes networks outside of the OSPF domain. Originated by the ASBR and passed between areas. In Stub and NSSA area, LSA Type 5 routes are replaced with a single default route.


6 LSA Type 6 are called group-membership-LSAs. Used to identify the location of Multicast group members in MOSPF.


7 LSA Type 7 are used in OSPF NSSA areas to import external routes.

Translated between areas.

8.2.1 Normal Areas

A normal area is simply a collection of routers using the same Area-ID that calculates inter-area and external routes through the use of summary-LSAs, ASBR-summary-LSAs, and AS-external-LSAs. A Normal Area supports ABR and ASBRs.

Figure 5: Normal Areas

8.2.1.1 Configuring the ABR

There is no configuration parameter to configure a Ethernet Routing Switch 8600 as an ABR. It becomes an ABR automatically when more than one area is configured on it.

8.2.1.2 Configuring the ASBR

When configuring an OSPF ASBR on the Ethernet Routing Switch 8600, it can be configured to:

Distribute all OSPF routes to BGP or RIP.

Distribute RIP, BGP, Direct, or static routes to OSPF


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To configure a Ethernet Routing Switch 8600 as an ASBR, use the following command

PP8600A# config ip ospf as-boundary-router enable

8.2.1.3 Configuration Example - Configuring the ABR

On the Ethernet Routing Switch 8600, there are no configuration steps to enable a Ethernet Routing Switch 8600 for ABR. As soon as more than one area is configured, the Ethernet Routing Switch 8600 is automatically configured as an OSPF ABR. The following is an example on how to add an OSPF interface to a new area:

Figure 6: ABR Configuration Example

In reference to PP8600B, the following commands are used to configure it for area 0.0.0.2 and area 0.0.0.0 thereby making it an OSPF ABR.

PP8600B Configuration Steps

Step 1 Configure OSPF Interface


2090


These two command configure port 2/6 as a brouter port and enables OSPF on this interface

Step 2 Configure Second OSPF Interface


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Step 3 Create Circuitless IP


1.1.1.2/255.255.255.255


enable

These commands create a circuitless IP address which will be used for the OSPF Router-ID


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Step 4 Enable OSPF

ip ospf router-id 1.1.1.2

ip ospf enable

ip ospf area 0.0.0.2 create

ip ospf interface 10.1.1.17 area 0.0.0.2

These commands configure the PP8600 as border router. Note by default, OSPF interface 10.1.1.22 is by default put into OSPF area 0.0.0.0. Since we added one additional area of 0.0.0.2, PP8600B automatically becomes an ABR.

To view the area‟s created use the following command:

PP8600B# show ip ospf area

================================================================================

Ospf Area

================================================================================

AREA_ID STUB_AREA NSSA IMPORT_SUM ACTIVE_IFCNT

--------------------------------------------------------------------------------

0.0.0.0 false false true 2

0.0.0.2 false false true 1

STUB_COST SPF_RUNS BDR_RTR_CNT ASBDR_RTR_CNT LSA_CNT LSACK_SUM

--------------------------------------------------------------------------------

0 61 2 0 18 565959

1 28 2 1 19 606498

You can use the following command to view the ABR status:

PP8600A# show ip ospf info

Ospf General

================================================================================

RouterId: 1.1.1.2

AdminStat: enabled

VersionNumber: 2

AreaBdrRtrStatus: true ◄

ASBdrRtrStatus: false

ExternLsaCount: 1

ExternLsaCksumSum: 29660(0x73dc)

TOSSupport: 0

OriginateNewLsas: 270

RxNewLsas: 1047

TrapEnable: false

AutoVirtLinkEnable: false

SpfHoldDownTime: 10


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8.2.2 Stub Area

A stub area does not receive advertisements for external routes (AS-external LSAs, type 5) from an Area Border Router, which reduces the size of the link state database. Instead, routing to external destinations from within a stub area is based simply on the default route originated by a stub area border router. A stub area has only one area border router. Any packets destined outside the area are simply routed to that area border exit point where the packets are examined by the area border router and forwarded to a destination. ASBR‟s cannot be supported within a stub area. Without AS-external LSA‟s, stub area‟s cannot support virtual links.

8.2.2.1 Configuring a Stub Area

To configure an OSPF area as a stub or NSSA, use the following command

PP8600A# config ip ospf area <area IP address> stub <true | false>

PP8600A# config ip ospf area <area IP address> nssa <true | false>

AS-external LSA‟s are not flooded into a Stub area‟s. Instead, only one default route to external destinations is distributed into the Stub area by the Stub ABR router

8.2.2.1.1 Configuration Example – Stub Area Configuration

Figure 7: Stub Area Example

The following are the configuration step required on PP8600E and PP8600B:

PP8600E Configuration Steps:



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Step 2 Configure VLAN 2



config vlan 2 ip create

172.3.3.1/255.255.255.0

vlan 2 ip ospf enable

These command create VLAN = 2 and enabled ospf for this interface.



1.1.1.5/255.255.255.255


enable


Step 4 Enable OSPF


ip ospf enable


ip ospf area 0.0.0.2 stub true




These commands configure the PP8600 as stub area 2, assigns the Circuitless IP created in Step 2 as the OSPF Router-ID, and finally adds the OSPF interfaces to Area 2.

PP8600E Configuration Steps:



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Step 2 Configure Second OSPF Interface


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1.1.1.2/255.255.255.255


enable



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Step 4 Enable OSPF


ip ospf enable




These commands configure the PP8600 as stub border router. Note by default, OSPF interface 10.1.1.22 is by default put into OSPF area 0.0.0.0. Since we added one additional sub area of 0.0.0.2, PP8600B automatically becomes an stub ABR.

NSSA

A not so stubby area (NSSA) also prevents the flooding of AS-External Link State advertisements into the area by replacing them with a default route. The added feature of NSSA is the ability to import small stub (non-OSPF) routing domains into OSPF. This allows the NSSA to import external routes such as RIP routes and then advertise these routes throughout the network. External routing information is imported into a NSSA by using Type-7 LSAs. These LSA‟s are translated at the NSSA boundary into LSA Type-5. The N/P bit in the Type-7 LSA Options field indicates whether the Type-7 LSA should be translated. Only those LSA‟s with the N/P-bit set are translated.

Figure 8: NSSA

8.2.2.1.2 Configuration Example – Configuring an NSSA Area

Figure 9: NSSA Configuration Example


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Step 1 Configure RIP Interface


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config ethernet 1/48 ip rip enable

These two command configure port 1/48 as a brouter port and enables RIP on this interface

Step 2 Enable RIP Globally and Configure RIP Interface for RIPv2

config ip rip enable

config ip rip interface 20.1.1.2 send-mode

rip2

config ip rip interface 20.1.1.2 receive-

mode rip2



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1.1.1.5/255.255.255.255


enable


Step 5 Enable OSPF

ip ospf as-boundary-router enable


ip ospf enable


ip ospf area 0.0.0.2 nssa true



These commands configure the PP8600 as an ASBR, assigns the Circuitless IP created in Step 4 as the OSPF Router-ID, creates OSPF NSSA area 2, and finally adds the OSPF interfaces to Area 2.

Step 6 Configure a Route Policy to distribute direct and OSPF to RIP

config ip route-policy "Rip_Dist" seq 1

create


enable


action permit


match-protocol local|ospf


These commands create a route policy named “Rip_Dist” that distribute directly connected and OSPF routes into RIP


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set-metric-type type1

Step 7 Apply Route Policy to RIP Out-Policy

ip rip interface 20.1.1.2 out-policy

"Rip_Dist"

Step 8 Configure OSPF route distribution to distribute RIP routes as AS-external-LSA Type 1

config ip ospf redistribute rip create

config ip ospf redistribute rip metric-

type type1

config ip ospf redistribute rip enable

9. Configuration Examples

OSPF Route Distribution to RIP, RIP to OSPF 9.1(AS-external-LSA Type 1 Metrics)

Figure 10: OSPF ASBR Configuration Example

To configure a Ethernet Routing Switch 8600 as an OSPF ASBR and distribute all OSPF routes to RIP and RIP to OSPF, perform the following steps:


config ethernet 1/31 ip create

10.1.1.41/30 2136


These two commands configure port 1/31 as a brouter port and enables RIP on this interface


config ip rip interface 10.1.1.41 send-

mode rip2


mode rip2

These commands enable RIP and configures the RIP interface for RIPv2 mode only.



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These two commands configure port 2/7 as a brouter port and enables OSPF on this interface


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1.1.1.3/32


enable

This step creates a circuitless IP address which will be used for the OSPF Router-ID

Step 4 Enable OSPF

config ip ospf as-boundary-router enable



These commands configure the PP8600 as an ASBR and assigns the Circuitless IP created in Step 3 as the OSPF Router-ID



config ip ospf redistribute rip metric 10


type type1


These commands configure OSPF router distribution to import RIP into OSPF. In turn, PP8600C will distribute the RIP routes as AS-external-LSA using external metric Type 1.

AS-external LSA‟s are not flooded into a Stub area‟s. Instead, only one default route to external destinations is distributed into the Stub area by the Stub ABR router

Step 6 Configure a Route Policy to distribute OSPF and Direct interfaces to RIP

config ip route-policy "Allow" seq 1

create


enable


action permit



These commands will create a Route Policy named “Allow” and will distribute both local interfaces and OSPF.


config ip rip interface 10.1.1.41 out-

policy "Allow"

This command applies the Route Policy created in Step 1 to RIP interface 10.1.1.41.


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The above procedure is fine if you don‟t have a large OSPF network, as all OSPF routes will be distributed to RIP. Instead, you can configure the Ethernet Routing Switch 8600 ASBR to distribute only a default route instead of all OSPF routes to RIP.

Step 1 Configure a IP Prefix List with a Default Route

config ip prefix-list "default" add-prefix

0.0.0.0/0

This command creates an IP Prefix list named “default” with address 0.0.0.0/0


config ip route-policy "Policy_Default"

seq 1 create


seq 1 enable


seq 1 action permit


seq 1 match-protocol ospf


seq 1 set-injectlist "default"


seq 1 set-metric-type type1

These commands will create a Route Policy named “Policy_Default” and will distribute the IP Prefix list created in Step 1. Notice that ospf is selected for match-protocol. Hence, the default route will only be advertised via RIP if OSPF is up.


config ip rip interface 10.1.1.41 out-

policy "Policy_Default"

This command applies the Route Policy created in Step 2 to RIP interface 10.1.1.41.


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Distributing an Internet Default Route to OSPF 9.2using AS-external-LSA Type 2

The following is an example on how to configure an OSPF ASBR to distribute a default route for Internet traffic.

Figure 11: Distributing Default Route to OSPF



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1.1.1.1/32


enable

This step creates a circuitless IP address which will be used for both the OSPF Router-ID and BGP identifier.

Step 3 Enable OSPF




These commands configure the PP8600 as an ASBR and assigns the Circuitless IP created in Step 2 as the OSPF Router-ID

Step 4 Configure the BGP Interface

config ethernet 1/2 ip create

131.168.1.2/30 2065

config ip bgp local-as 65500

config ip bgp enable

config ip bgp neighbor 131.168.1.1 create

config ip bgp neighbor 131.168.1.1 remote-

as 65503

config ip bgp neighbor 131.168.1.1 admin-

state enable


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Step 5 Configure a Prefix List with the default route

config ip prefix-list "Default_Prefix"

add-prefix 0.0.0.0/0

This commands add a Prefix List with the default route which will be used in Step 6.

Step 6 Configure a Route Policy to distribute for default route distribution

config ip route-policy "Default_Route" seq

1 create


1 enable


1 action permit


1 set-injectlist "Default_Prefix"


1 set-metric 100


1 set-metric-type type2

These commands create a Route Policy named „Default-Route” and adds the Prefix List created in Step 5. Notice the external metric is set for Type 2.

Step 7 Configure OSPF Route Distribution

config ip ospf redistribute bgp create

config ip ospf redistribute bgp metric 1

config ip ospf redistribute bgp route-

policy "Default_Route"

config ip ospf redistribute bgp enable

These command enable BGP route importation into OSPF, but, distribute only a Default Route.

Please refer to the „Configure BGP Services‟ manual on how to distribute OSPF routes to BGP.

Viewing AS_External LSA’s

An ASBR will advertise, such as RIP routes from the example above, as AS_external LSA‟s (LSA Type 5). AS_external LSA‟s can viewed by using the following command:

ERS-8610:6# show ip ospf ase

================================================================================

Ospf AsExternal Lsas

================================================================================

LSTYPE LINKSTATEID ADV_ROUTER E_METRIC ASE_FWD_ADDR AGE SEQ_NBR CSUM

--------------------------------------------------------------------------------

AsExternal 0.0.0.0 1.1.1.1 1 100 0.0.0.0 276 0x8000015c 0x2fdc

AsExternal 15.15.15.0 1.1.1.2 1 2 10.1.1.18 262 0x800000ed 0xaa28

AsExternal 172.2.2.0 1.1.1.3 0 10 0.0.0.0 236 0x800000be 0x769d

You can also use the „show ip ospf lsdb‟ command to view all the LSA‟s including AS_External LSA‟s.


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Controlling External Routes Advertised in an 9.3NSSA Area

In an OSPF NSSA area, the NSSA N/b-bit in the Options field of OSPF Hello packets is used to tell the border router what external routes can be advertised to other areas. The NSSA N/p-bit, if set, tells the area border router to export the external route. This is the default behavior with the Ethernet Routing Switch 8600. Otherwise, if not set, it informs the area border router to drop the external route. A route policy can be created on the Ethernet Routing Switch 8600 manipulate the N/p-bit.

Figure 12: Controlling External Routes (NSSA Area)

In this configuration example, there is a RIP network inside the NSSA Area 2. We would like to only advertise the 15.15.15.0/24 network to Area 0. The following are the configuration step required on PP8600E:

Enable PP8600E as an OSPF ASBR

Create NSSA Area 2

Create a Route Policy to advertise OSPF and direct interfaces to RIP

Create a Route Policy to only advertise RIP network 15.15.15.0/24 to Area 0 by using the NSSA N/p-bit



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These two command configure port 1/48 as a brouter port and enables RIP on this interface

Step 2 Enable RIP Globally and Configure RIP Interface for RIPv2


config ip rip interface 20.1.1.2 send-mode

rip2


mode rip2


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1.1.1.5/255.255.255.255


enable


Step 5 Enable OSPF



ip ospf enable





These commands configure the PP8600 as an ASBR, assigns the Circuitless IP created in Step 4 as the OSPF Router-ID, creates OSPF NSSA area 2, and finally adds the OSPF interfaces to Area 2.

Step 6 Configure a Route Policy to distribute direct and OSPF to RIP


create


enable


action permit




set-metric-type type1


set-nssa-pbit enable

These commands create a route policy named “Rip_Dist” that distribute directly connected and OSPF routes into RIP


ip rip interface 20.1.1.2 out-policy

"Rip_Dist"

Step 8 Configure Prefix Lists

config ip prefix-list "15.15.15.0" add-

prefix 15.15.15.0/24

config ip prefix-list "14.14.14.0" add-

prefix 14.14.14.0/24

These commands add two Prefix Lists named “15.15.15.0” and “14.14.14.0” with pertaining to the networks from the RIP network.


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Step 9 Configure a Route Policy to set NSSA p-bit

config ip route-policy "P_bit" seq 1

create


enable


action permit


match-network "15.15.15.0"


match-protocol ospf

config ip route-policy "P_bit" seq 1 set-

nssa-pbit enable


create


enable


action permit


match-network "14.14.14.0"


match-protocol ospf

config ip route-policy "P_bit" seq 2 set-

nssa-pbit disable

These commands create a Route Policy named “P_bit” that sets the NSSA N/P-bit only for the Prefix List named “15.15.15.0”.




type type1

config ip ospf redistribute rip route-

policy "P_bit"



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PP8600E Configuration File

#

# PORT CONFIGURATION - PHASE II

#

ethernet 1/48 ip create 20.1.1.2/255.255.255.252 2091 mac_offset 2

ethernet 1/48 ip rip enable


ethernet 2/6 ip ospf enable

ethernet 2/6 ip ospf priority 0

#

# IP PREFIX LIST CONFIGURATION

#

ip prefix-list "15.15.15.0" add-prefix 15.15.15.0/24 maskLenFrom 24 maskLenTo 24

ip prefix-list "14.14.14.0" add-prefix 14.14.14.0/24 maskLenFrom 24 maskLenTo 24

#

# IP ROUTE POLICY CONFIGURATION

#

ip route-policy "Rip_Dist" seq 1 create

ip route-policy "Rip_Dist" seq 1 enable

ip route-policy "Rip_Dist" seq 1 action permit

ip route-policy "Rip_Dist" seq 1 match-protocol local|ospf

ip route-policy "Rip_Dist" seq 1 set-metric-type type1

ip route-policy "Rip_Dist" seq 1 set-nssa-pbit enable

ip route-policy "P_bit" seq 1 create

ip route-policy "P_bit" seq 1 enable

ip route-policy "P_bit" seq 1 action permit

ip route-policy "P_bit" seq 1 match-network "15.15.15.0"

ip route-policy "P_bit" seq 1 match-protocol ospf

ip route-policy "P_bit" seq 1 set-metric-type type2

ip route-policy "P_bit" seq 1 set-nssa-pbit enable

ip route-policy "P_bit" seq 2 create

ip route-policy "P_bit" seq 2 enable

ip route-policy "P_bit" seq 2 action permit

ip route-policy "P_bit" seq 2 match-network "14.14.14.0"

ip route-policy "P_bit" seq 2 match-protocol ospf

ip route-policy "P_bit" seq 2 set-metric-type type2

ip route-policy "P_bit" seq 2 set-nssa-pbit disable

ip rip enable

ip rip interface 20.1.1.2 send-mode rip2


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ip rip interface 20.1.1.2 receive-mode rip2

#

# CIRCUITLESS IP INTERFACE CONFIGURATION

#

ip circuitless-ip-int 1 create 1.1.1.5/255.255.255.255

ip circuitless-ip-int 1 ospf enable

#

# OSPF CONFIGURATION

#

ip ospf admin-state enable



ip ospf enable




ip ospf interface 10.1.1.18 add-message-digest-key 1 md5-key Test



#

# IP REDISTRIBUTION CONFIGURATION

#

ip ospf redistribute rip create

ip ospf redistribute rip metric-type type1

ip ospf redistribute rip route-policy "P_bit"

ip ospf redistribute rip enable

#

# RIP POLICY CONFIGURATION

#

ip rip interface 20.1.1.2 out-policy "Rip_Dist"


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Route Summarization between Area’s 9.4

In this example, we wish to

Use brouter ports for all core links

Configure port based VLANs for local networks.

Configure PP8600A to add a default route pointing to the Network Core and advertise the default route to PP8600B and PP8600C.

Adjusting OSPF Timers 9.5

By default, the OSPF timers are set as follows:

Hello Interval = 10 seconds (how often OSPF hello‟s are sent)

o The time interval to show often OSPF hello packets are sent.

Dead Interval = 40 seconds

o The time interval that sets the number of seconds without receiving Hello packets before an OSPF neighbor adjacency is declared down.

o The timer is normally set to 4 x the OSPF Hello interval

SPF (Shortest path first) Hold Down = 10 seconds

o The interval in which the router refuses to accept updates (LSA) for a route has been declared unreachable.

Without changing any of the default OSPF parameters, by default, it will take 40 seconds before declaring a neighbor‟s adjacency is down. For networks that require a faster convergence, the Hello Timer can set down to as low as 1 seconds with a dead interval of 4 seconds and a hold down of 4 seconds. On the Ethernet Routing Switch 8600, the Hello and Dead interval are configurable on a interface level while the hold down is an OSPF global parameter.

To change the default OSPF timer setting, the following commands are used:

To change the OSPF hello timer, enter the following command:

ERS 8600# config ip ospf interface <IP address> hello-interval <1-65535>

To change the OSPF Dead Interface, enter the following command:


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ERS 8600# config ip ospf interface <IP address> dead-interval <0..2147483647>

To change the OSPF Hold Down Interface, enter the following command:

ERS 8600# config ip ospf holddown <3..60>

Complex Configuration Example: 9.6

This section has configuration examples for five Ethernet Routing Switch 8600‟s pertaining to the diagram below:

PP8600A is an OSPF ASBR belonging to OSPF Area 0 and 3. It also configured to distribute a default route for Internet traffic.

PP8600B is an OSPF Stub ABR to OSPF Area 2 and ABR to OSPF Area 3

PP8600C is an OSPF ASBR and is configured to distribute OSPF to RIP and RIP to OSPF

PP8600D is an OSPF internal router in Area 3

PP8600E is an internal OSPF Sub router in Area 2

All OSPF interfaces will be brouter ports with the exception of PP8600E. For network 172.3.3.0/24 on PP8600E, VLAN configuration will be used instead of brouter port. The reason for using brouter ports versus VLANs is spanning tree is disable by default by using brouter interfaces.

All interfaces used for this configuration are Ethernet, hence OSPF interfaces are broadcast with the exception of the Circuitless IP interfaces which are passive. PP8600E is configured so that if never becomes a Designated Router (DR) by setting it‟s interface priority to 0.

Setup OSPF Router Priority so that PP8600A becomes DR (priority = 100) and PP8600B becomes BDR (priority = 50).

The reason for using Stub or NSSA areas is to reduce the LSDB size by not including external LSA‟s. The Sub ABR will advertise a default route into the Stub area for all external routes.

Figure 14: PP8600 Network Example


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PP8600A

#


#

ethernet 1/2 auto-negotiate disable

ethernet 1/2 speed 100

ethernet 1/2 duplex full








#

# IP PREFIX LIST CONFIGURATION

#

ip prefix-list "Default_Prefix" add-prefix 0.0.0.0/0 maskLenFrom 0 maskLenTo 0

#


#

ip route-policy "Default_Route" seq 1 create

ip route-policy "Default_Route" seq 1 enable

ip route-policy "Default_Route" seq 1 action permit

ip route-policy "Default_Route" seq 1 set-injectlist "Default_Prefix"

ip route-policy "Default_Route" seq 1 set-metric 100

ip route-policy "Default_Route" seq 1 set-metric-type type2

ip route-policy "Default_Route" seq 1 set-nssa-pbit enable

#


#



#



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#




ip ospf enable



#

# BGP CONFIGURATION

#

ip bgp local-as 65500

ip bgp enable

ip bgp neighbor 131.168.1.1 create

ip bgp neighbor 131.168.1.1 remote-as 65503

ip bgp neighbor 131.168.1.1 route-advertisement-interval 30 add

ip bgp neighbor 131.168.1.1 admin-state enable

#


#

ip ospf redistribute bgp create

ip ospf redistribute bgp metric 1

ip ospf redistribute bgp route-policy "Default_Route"

ip ospf redistribute bgp enable

PP8600B

Since PP8600B belongs to three area‟s with one being a stub area, it will be configured for an Stub ABR.

#


#










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#


#



#


#



ip ospf enable






PP8600C

#


#


ethernet 1/31 ip rip enable

ethernet 1/31 ip rip default-supply enable





#


#

ip route-policy "Allow" seq 1 create

ip route-policy "Allow" seq 1 enable

ip route-policy "Allow" seq 1 action permit

ip route-policy "Allow" seq 1 match-protocol local|ospf


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ip route-policy "Allow" seq 1 set-metric-type type2

ip route-policy "Allow" seq 1 set-nssa-pbit enable

ip rip enable

ip rip interface 10.1.1.41 send-mode rip2

ip rip interface 10.1.1.41 receive-mode rip2

#


#



#


#




ip ospf enable


ip ospf interface 10.1.1.41 create broadcast




#


#

ip ospf redistribute rip create

ip ospf redistribute rip metric 10

ip ospf redistribute rip enable

#

# RIP POLICY CONFIGURATION

#

ip rip interface 10.1.1.41 out-policy "Allow"


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PP8600D Configuration

#


#





#


#



#


#



ip ospf enable





PP8600E Configuration

#

# VLAN CONFIGURATION

#

vlan 1 ports remove 1/1-1/48,2/1-2/8 member portmember

vlan 2 create byport 1 color 1

vlan 2 ports remove 1/3-1/48,2/1-2/8 member portmember

vlan 2 ports add 1/1-1/2 member portmember

vlan 2 ip create 172.3.3.1/255.255.255.0 mac_offset 0


vlan 2 ip ospf priority 0


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#


#




#


#



#


#



ip ospf enable







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10. Appendix

The following CLI strings are intended to be used in a cut and paste manner to facilitate Ethernet Routing Switch 8600 OSPF configurations. Please reference the associated figure and configuration notes in that section then use the Acrobat "Text Select Tool" to copy the commands and paste in a provisioning window, edit associated parameters as required.

Circuitless IP (CLIP) CLI 10.1

Reference Section 2 (page 4):

config ip circuitless-ip-int X create <ipaddress/mask>

config ip circuitless-ip-int X ospf enable

config ip ospf admin-state enable

config ip ospf router-id <CLIP IP Address>


OSPF Brouter Port CLI 10.2

Reference Figure 1 (page 5) and the configuration tables on page 5:

config ethernet 2/1 ip create 10.1.1.21/30 2134






config ip circuitless-ip-int 1 create 1.1.1.1/32

config ip circuitless-ip-int 1 ospf enable



OSPF Network CLI 10.3





config vlan 2 ip ospf interface-type passive



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MD5 Authentication CLI 10.4


config ip ospf interface 10.1.1.1 add-message-digest-key 1 md5-key qwsdf89

config ip ospf interface 10.1.1.1 authentication-type message-digest

config ip ospf interface 10.1.1.2 add-message-digest-key 1 md5-key qwsdf89

config ip ospf interface 10.1.1.2 authentication-type message-digest

Add OSPF Interface to New Area CLI 10.5


PP8600B Configuration:





config ip circuitless-ip-int 1 create 1.1.1.2/255.255.255.255



ip ospf enable



Stub Area CLI 10.6

Reference Figure 7 (page 16) and the configuration tables on pages 16-17:

Ethernet Routing Switch 8600E Configuration:





config vlan 2 ip create 172.3.3.1/255.255.255.0





ip ospf enable





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Ethernet Routing Switch 8600B Configuration:








ip ospf enable




NNSA ASBR Router CLI 10.7


Ethernet Routing Switch 8600E Configuration




config ip rip interface 20.1.1.2 send-mode rip2

config ip rip interface 20.1.1.2 receive-mode rip2







ip ospf enable





config ip route-policy "Rip_Dist" seq 1 create

config ip route-policy "Rip_Dist" seq 1 enable

config ip route-policy "Rip_Dist" seq 1 action permit

config ip route-policy "Rip_Dist" seq 1 match-protocol local|ospf


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config ip route-policy "Rip_Dist" seq 1 set-metric-type type1



config ip ospf redistribute rip metric-type type1


OSPF ASBR CLI 10.8


Ethernet Routing Switch 8600C Configuration:














config ip ospf redistribute rip metric 10



config ip route-policy "Allow" seq 1 create

config ip route-policy "Allow" seq 1 enable

config ip route-policy "Allow" seq 1 action permit

config ip route-policy "Allow" seq 1 match-protocol local|ospf

config ip rip interface 10.1.1.41 out-policy "Allow"

To configure the Ethernet Routing Switch 8600 ASBR to distribute only a default route instead of

all OSPF routes to RIP:

config ip prefix-list "default" add-prefix 0.0.0.0/0

config ip route-policy "Policy_Default" seq 1 create

config ip route-policy "Policy_Default" seq 1 enable

config ip route-policy "Policy_Default" seq 1 action permit

config ip route-policy "Policy_Default" seq 1 match-protocol ospf


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config ip route-policy "Policy_Default" seq 1 set-injectlist "default"

config ip route-policy "Policy_Default" seq 1 set-metric-type type1

config ip rip interface 10.1.1.41 out-policy "Policy_Default"

Default Route to OSPF CLI 10.9


Ethernet Routing Switch 8600A Configuration:









config ip bgp local-as 65500

config ip bgp enable

config ip bgp neighbor 131.168.1.1 create

config ip bgp neighbor 131.168.1.1 remote-as 65503

config ip bgp neighbor 131.168.1.1 admin-state enable

config ip prefix-list "Default_Prefix" add-prefix 0.0.0.0/0

config ip route-policy "Default_Route" seq 1 create

config ip route-policy "Default_Route" seq 1 enable

config ip route-policy "Default_Route" seq 1 action permit

config ip route-policy "Default_Route" seq 1 set-injectlist "Default_Prefix"

config ip route-policy "Default_Route" seq 1 set-metric 100

config ip route-policy "Default_Route" seq 1 set-metric-type type2

config ip ospf redistribute bgp create

config ip ospf redistribute bgp metric 1

config ip ospf redistribute bgp route-policy "Default_Route"

config ip ospf redistribute bgp enable

** Please refer to the „Configure BGP Services‟ manual on how to distribute OSPF

routes to BGP.


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Controlling External Routes (NSSA Area) CLI 10.10


Ethernet Routing Switch 8600E Configuration:












ip ospf enable





config ip route-policy "Rip_Dist" seq 1 create

config ip route-policy "Rip_Dist" seq 1 enable

config ip route-policy "Rip_Dist" seq 1 action permit

config ip route-policy "Rip_Dist" seq 1 match-protocol local|ospf

config ip route-policy "Rip_Dist" seq 1 set-metric-type type1

config ip route-policy "Rip_Dist" seq 1 set-nssa-pbit enable


config ip prefix-list "15.15.15.0" add-prefix 15.15.15.0/24

config ip prefix-list "14.14.14.0" add-prefix 14.14.14.0/24

config ip route-policy "P_bit" seq 1 create

config ip route-policy "P_bit" seq 1 enable

config ip route-policy "P_bit" seq 1 action permit

config ip route-policy "P_bit" seq 1 match-network "15.15.15.0"

config ip route-policy "P_bit" seq 1 match-protocol ospf

config ip route-policy "P_bit" seq 1 set-nssa-pbit enable

config ip route-policy "P_bit" seq 2 create

config ip route-policy "P_bit" seq 2 enable

config ip route-policy "P_bit" seq 2 action permit

config ip route-policy "P_bit" seq 2 match-network "14.14.14.0"


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config ip route-policy "P_bit" seq 2 match-protocol ospf

config ip route-policy "P_bit" seq 2 set-nssa-pbit disable



config ip ospf redistribute rip route-policy "P_bit"



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11. Software Baseline

This document is based on Ethernet Routing Switch 8600 Software Release 3.5.

12. Reference Documentation

Publication Number Document Title

314720-C Rev 00May 2003

Configuring IP Routing Operations


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© 2010 Avaya Inc. All Rights Reserved.

Avaya and the Avaya Logo are trademarks of Avaya Inc. and are registered in the United States and other countries. All trademarks identified by ®, TM or SM are registered marks, trademarks, and service marks, respectively, of Avaya Inc. All other trademarks are the property of their respective owners. Avaya may also have trademark rights in other terms used herein. References to Avaya include the Nortel Enterprise business, which was acquired as of December 18, 2009.

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Ethernet Routing Switch 8600/8800 - Avaya