Contents

Introduction· 1

Prerequisites· 1

Example: Configuring IS-IS·· 1

Network configuration· 1

Analysis· 2

Applicable hardware and software versions· 2

Restrictions and guidelines· 4

Procedures· 4

Configuring Switch A· 4

Configuring Switch B· 4

Configuring Switch C· 5

Configuring Switch D·· 5

Configuring Switch E· 6

Verifying the configuration· 6

Configuration files· 8

 

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:

·     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 allow communication between the marketing department and the finance department, configure Switch A and Switch B in Area 10 as Level-1 routers.

To allow communication between the marketing department and the partner, configure route redistribution between IS-IS and OSPF on Switch D.

To ensure that the branch does not have a route to the finance department, configure Switch C to use a prefix list to advertise only network 10.100.1.0/24 to Level-2.

To ensure that the communication is not interrupted when the IS-IS process on Switch C restarts, enable IS-IS Graceful Restart (GR) on Switch C.

Applicable hardware and software versions

The following matrix shows the hardware and software versions to which this configuration example is applicable:

 

Hardware	Software version
S6812 switch series S6813 switch series	Release 66xx
S6550XE-HI switch series	Release 6008 and later
S6525XE-HI switch series	Release 6008 and later
S5850 switch series	Release 8005 and later
S5570S-EI switch series	Release 11xx
S5560X-EI switch series	Release 63xx, Release 65xx, Release 66xx
S5560X-HI switch series	Release 63xx, Release 65xx, Release 66xx
S5500V2-EI switch series	Release 63xx, Release 65xx, Release 66xx
MS4520V2-30F switch	Release 63xx, Release 65xx, Release 66xx
MS4520V2-30C switch MS4520V2-54C switch	Release 65xx, Release 66xx
MS4520V2-28S switch MS4520V2-24TP switch	Release 63xx
S6520X-HI switch series S6520X-EI switch series	Release 63xx, Release 65xx, Release 66xx
S6520X-SI switch series S6520-SI switch series	Release 63xx, Release 65xx, Release 66xx
S5000-EI switch series	Release 63xx, Release 65xx, Release 66xx
MS4600 switch series	Release 63xx, Release 65xx, Release 66xx
S5560S-EI switch series S5560S-SI switch series	Release 63xx
S5500V3-24P-SI S5500V3-48P-SI	Release 63xx
S5500V3-SI switch series (except S5500V3-24P-SI and S5500V3-48P-SI)	Release 11xx
S5170-EI switch series	Not supported
S5130S-HI switch series S5130S-EI switch series S5130S-SI switch series S5130S-LI switch series	Not supported
S5120V2-SI switch series S5120V2-LI switch series	Not supported
S5120V3-EI switch series	Not supported
S5120V3-36F-SI S5120V3-28P-HPWR-SI S5120V3-54P-PWR-SI	Not supported
S5120V3-SI switch series (except S5120V3-36F-SI, S5120V3-28P-HPWR-SI, and S5120V3-54P-PWR-SI)	Not supported
S5120V3-LI switch series	Not supported
S3600V3-EI switch series	Release 11xx
S3600V3-SI switch series	Not supported
S3100V3-EI switch series S3100V3-SI switch series	Not supported
S5110V2 switch series	Not supported
S5110V2-SI switch series	Not supported
S5000V3-EI switch series S5000V5-EI switch series	Not supported
S5000E-X switch series S5000X-EI switch series	Not supported
E128C switch E152C switch E500C switch series E500D switch series	Not supported
MS4320V2 switch series MS4320V3 switch series MS4300V2 switch series MS4320 switch series MS4200 switch series	Not supported
WS5850-WiNet switch series	Release 63xx
WS5820-WiNet switch series WS5810-WiNet switch series	Not supported
WAS6000 switch series	Not supported
IE4300-12P-AC switch IE4300-12P-PWR switch IE4300-M switch series IE4320 switch series	Not supported

 

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 10.1921.6802.0001.00

[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 marketing department 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 Switch A.

[SwitchA] ping 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=254 time=1.862 ms

56 bytes from 10.200.1.1: icmp_seq=1 ttl=254 time=2.969 ms

56 bytes from 10.200.1.1: icmp_seq=2 ttl=254 time=1.402 ms

56 bytes from 10.200.1.1: icmp_seq=3 ttl=254 time=1.324 ms

56 bytes from 10.200.1.1: icmp_seq=4 ttl=254 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 13.13.13.3: icmp_seq=2 ttl=254 time=1.672 ms

56 bytes from 13.13.13.3: icmp_seq=3 ttl=254 time=1.751 ms

56 bytes from 13.13.13.3: icmp_seq=4 ttl=254 time=1.816 ms

56 bytes from 13.13.13.3: 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

#

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

#

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

#