H3C IS-IS Configuration Examples

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Copyright © 2017 New H3C Technologies Co., Ltd. All rights reserved. No part of this manual may be reproduced or transmitted in any form or by any means without prior written consent of New H3C Technologies Co., Ltd. The information in this document is subject to change without notice.

 

Contents

Introduction· 1

Prerequisites· 1

Example: Configuring IS-IS· 1

Network configuration· 1

Analysis· 2

Software versions used· 2

Restrictions and guidelines· 2

Procedures· 3

Configuring Switch A· 3

Configuring Switch B· 3

Configuring Switch C· 3

Configuring Switch D·· 4

Configuring Switch E· 5

Verifying the configuration· 5

Configuration files· 7

Related documentation· 10

 

Introduction

This document provides IS-IS configuration examples.

Prerequisites

The configuration examples in this document were created and verified in a lab environment, and all the devices were started with the factory default configuration. When you are working on a live network, make sure you understand the potential impact of every command on your network.

This document assumes that you have basic knowledge of IS-IS.

Example: Configuring IS-IS

Network configuration

As shown in Figure 1, the company's headquarters and the branch run IS-IS. The partner runs OSPF.

Configure the switches to meet the following requirements:

·     Reduce traffic for Switch A and Switch B because they have relative low performance.

·     The Marketing department can reach the Finance department, the branch, and the partner.

·     The Finance department and the branch cannot reach each other, and the branch does not have a route to the Finance department.

·     When the IS-IS process on Switch C restarts, the communication is not interrupted.

Figure 1 Network diagram

 

Analysis

To meet the network requirements, you must perform the following tasks:

·     To reduce traffic for Switch A and Switch B, configure them as Level-1 routers to allow communication only between the Marketing department and the Finance department.

·     Configure route redistribution between IS-IS and OSPF on Switch D to allow communication between the Marketing department and the partner.

·     Configure Switch C to use a prefix list to advertise only network 10.100.1.0/24 to Level-2 to ensure that the branch does not have a route to the Finance department.

·     Enable IS-IS Graceful Restart (GR) on Switch C to ensure that the communication is not interrupted when the IS-IS process on Switch C restarts.

Software versions used

This configuration example was created and verified on S7500X-CMW710-R7536P05.

Restrictions and guidelines

To avoid blackhole routes, do not change the network topology during the IS-IS GR process.

Procedures

Configuring Switch A

# Configure an IP address for VLAN-interface 11.

<SwitchA> system-view

[SwitchA] interface vlan-interface 11

[SwitchA-Vlan-interface11] ip address 192.168.1.1 24

[SwitchA-Vlan-interface11] quit

# Configure IP addresses for other interfaces, as shown in Figure 1. (Details not shown.)

# Configure IS-IS.

[SwitchA] isis 1

[SwitchA-isis-1] is-level level-1

[SwitchA-isis-1] network-entity 10.1921.6800.1001.00

[SwitchA-isis-1] quit

[SwitchA] interface vlan-interface 11

[SwitchA–Vlan-interface11] isis enable 1

[SwitchA–Vlan-interface11] quit

[SwitchA] interface vlan-interface 100

[SwitchA–Vlan-interface100] isis enable 1

[SwitchA–Vlan-interface100] quit

Configuring Switch B

# Configure an IP address for VLAN-interface 12.

<SwitchB> system-view

[SwitchB] interface vlan-interface 12

[SwitchB-Vlan-interface12] ip address 192.168.2.1 24

[SwitchB-Vlan-interface12] quit

# Configure IP addresses for other interfaces, as shown in Figure 1. (Details not shown.)

# Configure IS-IS.

[SwitchB] isis 1

[SwitchB-isis-1] is-level level-1

[SwitchB-isis-1] network-entity 10.1921.6800.2001.00

[SwitchB-isis-1] quit

[SwitchB] interface vlan-interface 12

[SwitchB–Vlan-interface12] isis enable 1

[SwitchB–Vlan-interface12] quit

[SwitchB] interface vlan-interface 200

[SwitchB–Vlan-interface 200] isis enable 1

[SwitchB–Vlan-interface 200] quit

Configuring Switch C

# Configure an IP address for VLAN-interface 11.

<SwitchC> system-view

[SwitchC] interface vlan-interface 11

[SwitchC-Vlan-interface11] ip address 192.168.1.2 24

[SwitchC-Vlan-interface11] quit

# Configure IP addresses for other interfaces, as shown in Figure 1. (Details not shown.)

# Configure IS-IS.

[SwitchC] isis 1

[SwitchC-isis-1] network-entity 10.1921.6801.0001.00

[SwitchC-isis-1] quit

[SwitchC] interface vlan-interface 10

[SwitchC–Vlan-interface10] isis enable 1

[SwitchC–Vlan-interface10] quit

[SwitchC] interface vlan-interface 11

[SwitchC–Vlan-interface11] isis enable 1

[SwitchC–Vlan-interface11] quit

[SwitchC] interface vlan-interface 12

[SwitchC–Vlan-interface12] isis enable 1

[SwitchC–Vlan-interface12] quit

# Configure route leaking from Level-1 to Level-2, and use prefix list 1 to advertise only network 10.100.1.0/24 to Level-2.

[SwitchC] ip prefix-list 1 permit 10.100.1.0 24

[SwitchC] isis 1

[SwitchC-isis-1] address-family ipv4

[SwitchC-isis-1-ipv4] import-route isis level-1 into level-2 filter-policy prefix-list 1

[SwitchC-isis-1-ipv4] quit

# Enable IS-IS GR.

[SwitchC-isis-1] graceful-restart

[SwitchC-isis-1] quit

Configuring Switch D

# Configure an IP address for VLAN-interface 10.

<SwitchD> system-view

[SwitchD] interface vlan-interface 10

[SwitchD- Vlan-interface10] ip address 192.168.10.2 24

[SwitchD- Vlan-interface10] quit

# Configure IP addresses for other interfaces, as shown in Figure 1. (Details not shown.)

# Configure IS-IS.

[SwitchD] isis 1

[SwitchD-isis-1] is-level level-2

[SwitchD-isis-1] network-entity 20.1921.6802.0001.00

[SwitchD-isis-1] quit

[SwitchD] interface vlan-interface 10

[SwitchD–Vlan-interface10] isis enable 1

[SwitchD–Vlan-interface10] quit

[SwitchD] interface vlan-interface 20

[SwitchD–Vlan-interface20] isis enable 1

[SwitchD–Vlan-interface20] quit

# Configure OSPF.

[SwitchD] ospf

[SwitchD-ospf-1] area 0

[SwitchD-ospf-1-area-0.0.0.0] network 192.168.20.0 0.0.0.255

[SwitchD-ospf-1-area-0.0.0.0] quit

[SwitchD-ospf-1] quit

# Redistribute OSPF and direct routes into IS-IS

[SwitchD] isis 1

[SwitchD-isis-1] address-family ipv4

[SwitchD-isis-1-ipv4] import-route ospf

[SwitchD-isis-1-ipv4] import-route direct

[SwitchD-isis-1-ipv4] quit

[SwitchD-isis-1] quit

# Redistribute IS-IS and direct routes into OSPF.

[SwitchD] ospf 1

[SwitchD-ospf-1] import-route isis 1

[SwitchD-ospf-1] import-route direct

Configuring Switch E

# Configure an IP address for VLAN-interface 20.

<SwitchE> system-view

[SwitchE] interface vlan-interface20

[SwitchE-Vlan-interface12] ip address 192.168.20.2 24

[SwitchE-Vlan-interface12] quit

# Configure IP addresses for other interfaces, as shown in Figure 1. (Details not shown.)

# Configure OSPF.

[SwitchE] ospf

[SwitchE-ospf-1] area 0

[SwitchE-ospf-1-area-0.0.0.0] network 192.168.20.0 0.0.0.255

[SwitchE-ospf-1-area-0.0.0.0] network 10.200.1.0 0.0.0.255

[SwitchE-ospf-1-area-0.0.0.0] quit

[SwitchE-ospf-1] quit

Verifying the configuration

# Verify that the branch can reach the Marketing department, but cannot reach the Finance department.

[SwitchD] display isis route

 

                         Route information for IS-IS(1)

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

 

                         Level-2 IPv4 Forwarding Table

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

 

 IPv4 Destination     IntCost    ExtCost ExitInterface   NextHop         Flags

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

 192.168.10.0/24      10         NULL    Vlan10          Direct          D/L/-

 192.168.1.0/24       20         NULL    Vlan10          192.168.10.1    R/-/-

 10.100.1.0/24        30         NULL    Vlan10          192.168.10.1    R/-/-

 192.168.2.0/24       20         NULL    Vlan10          192.168.10.1    R/-/-

 

      Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set

# Verify that the company can communicate with the partner.

·     Display the IS-IS routing table on Switch C.

[SwitchC] display isis route

 

                         Route information for IS-IS(1)

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

 

                         Level-1 IPv4 Forwarding Table

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

 

 IPv4 Destination     IntCost    ExtCost ExitInterface   NextHop         Flags

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

 192.168.10.0/24      10         NULL    Vlan10          Direct          D/L/-

 192.168.1.0/24       10         NULL    Vlan11          Direct          D/L/-

 10.100.1.0/24        20         NULL    Vlan11          192.168.1.1     R/L/-

 10.100.2.0/24        20         NULL    Vlan12          192.168.2.1     R/-/-

 192.168.2.0/24       10         NULL    Vlan12          Direct          D/L/-

 

      Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set

 

                         Level-2 IPv4 Forwarding Table

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

 

 IPv4 Destination     IntCost    ExtCost ExitInterface   NextHop         Flags

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

 192.168.10.0/24      10         NULL    Vlan10          Direct          D/L/-

 10.200.1.0/24        10         0       Vlan10          192.168.10.2    R/-/-

 192.168.20.0/24      10         0       Vlan10          192.168.10.2    R/-/-

 192.168.1.0/24       10         NULL    Vlan11          Direct          D/L/-

 192.168.2.0/24       10         NULL    Vlan12          Direct          D/L/-

 

      Flags: D-Direct, R-Added to Rib, L-Advertised in LSPs, U-Up/Down Bit Set

·     Ping 10.200.1.1 from the interface VLAN-interface 100 on Switch A.

[SwitchA] ping –a 10.1.1.1 10.200.1.1

Ping 10.200.1.1 (10.200.1.1): 56 data bytes, press CTRL_C to break

56 bytes from 10.200.1.1: icmp_seq=0 ttl=252 time=1.862 ms

56 bytes from 10.200.1.1: icmp_seq=1 ttl=252 time=2.969 ms

56 bytes from 10.200.1.1: icmp_seq=2 ttl=252 time=1.402 ms

56 bytes from 10.200.1.1: icmp_seq=3 ttl=252 time=1.324 ms

56 bytes from 10.200.1.1: icmp_seq=4 ttl=252 time=1.510 ms

 

--- Ping statistics for 10.200.1.1 ---

5 packet(s) transmitted, 5 packet(s) received, 0.0% packet loss

round-trip min/avg/max/std-dev = 1.324/1.813/2.969/0.606 ms

# Verify that the communication is not interrupted when the IS-IS process restarts.

·     Ping Switch B from Switch A.

[SwitchA] ping -c 10000 10.100.2.1

Ping 10.100.2.1 (10.100.2.1): 56 data bytes, press CTRL_C to break

56 bytes from 10.100.2.1: icmp_seq=0 ttl=254 time=1.185 ms

56 bytes from 10.100.2.1: icmp_seq=1 ttl=254 time=1.087 ms

…

·     Restart the IS-IS process on Switch C.

[SwitchC] reset isis all graceful-restart

Reset IS-IS process? [Y/N] :y

# Ping Switch B from Switch A.

[SwitchA] ping -c 10000 10.100.2.1

Ping 10.100.2.1 (10.100.2.1): 56 data bytes, press CTRL_C to break

56 bytes from 10.100.2.1: icmp_seq=0 ttl=254 time=1.185 ms

56 bytes from 10.100.2.1: icmp_seq=1 ttl=254 time=1.087 ms

56 bytes from 10.100.2.1: icmp_seq=2 ttl=254 time=1.672 ms

56 bytes from 10.100.2.1: icmp_seq=3 ttl=254 time=1.751 ms

56 bytes from 10.100.2.1: icmp_seq=4 ttl=254 time=1.816 ms

56 bytes from 10.100.2.1: icmp_seq=5 ttl=254 time=1.814 ms

# Check the IS-IS GR state on Switch C.

[SwitchC] display isis graceful-restart status

 

                        Restart information for IS-IS(1)

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

Restart status: COMPLETE

Restart phase: Finish

Restart t1: 3, count 10; Restart t2: 60; Restart t3: 300

SA Bit: supported

 

                          Level-1 restart information

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

Total number of interfaces: 3

Number of waiting LSPs: 0

 

                          Level-2 restart information

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

Total number of interfaces: 3

Number of waiting LSPs: 0

Configuration files

·     Switch A:

#

isis 1

 is-level level-1

 network-entity 10.1921.6800.1001.00

#

vlan 11

#

vlan 100

#

interface Vlan-interface11

 ip address 192.168.1.1 255.255.255.0

 isis enable 1

#

interface Vlan-interface100

 ip address 10.100.1.1 255.255.255.0

 isis enable 1

#

·     Switch B:

#

isis 1

 is-level level-1

 network-entity 10.1921.6800.2001.00

#

vlan 12

#

vlan 200

#

interface Vlan-interface12

 ip address 192.168.2.1 255.255.255.0

 isis enable 1

#

interface Vlan-interface200

 ip address 10.100.2.1 255.255.255.0

 isis enable 1

#

·     Switch C:

#

isis 1

 graceful-restart

 network-entity 10.1921.6801.0001.00

#

address-family ipv4 unicast

 import-route isis level-1 into level-2 filter-policy prefix-list 1

#

isis 1

 graceful-restart

 network-entity 10.1921.6801.0001.00

 #

 address-family ipv4 unicast

  import-route isis level-1 into level-2 filter-policy prefix-list 1

#

vlan 11 to 13

#

interface Vlan-interface11

 ip address 192.168.1.2 255.255.255.0

 isis enable 1

#

interface Vlan-interface12

 ip address 192.168.2.2 255.255.255.0

 isis enable 1

#

interface Vlan-interface13

 ip address 192.168.10.1 255.255.255.0

 isis enable 1

#

 ip prefix-list 1 index 10 permit 10.100.1.0 24

#

·     Switch D:

#

isis 1

 is-level level-2

 network-entity 20.1921.6802.0001.00

#

address-family ipv4 unicast

 import-route direct

 import-route ospf 1

 #

 address-family ipv4 unicast

  import-route direct

  import-route ospf 1

#

ospf 1

 import-route direct

 import-route isis 1

 area 0.0.0.0

  network 192.168.20.0 0.0.0.255

#

vlan 10

#

vlan 20

#

interface Vlan-interface10

 ip address 192.168.10.2 255.255.255.0

 isis enable 1

#

interface Vlan-interface20

 ip address 192.168.20.1 255.255.255.0

#

·     Switch E:

#

ospf 1

 area 0.0.0.0

  network 10.200.1.0 0.0.0.255

  network 192.168.20.0 0.0.0.255

#

vlan 20

#

vlan 300

#

interface Vlan-interface20

 ip address 192.168.20.2 255.255.255.0

#

interface Vlan-interface300

 ip address 10.200.1.1 255.255.255.0

#

Related documentation

·     H3C S7500X Switch Series Layer 3—IP Routing Command Reference-R7536P05

·     H3C S7500X Switch Series Layer 3—IP Routing Configuration Guide-R7536P05