H3C S5500-EI Series Operating instructions

Brand: H3C

Model: S5500-EI Series

Category: Network switches

Type: Operating instructions

Operation Manual – VRRP

H3C S5500-EI Series Ethernet Switches Table of Contents

Table of Contents

Chapter 1 VRRP Configuration....................................................................................................1-1

1.1 Introduction to VRRP.........................................................................................................1-1

1.1.1 VRRP Overview ......................................................................................................1-1

1.1.2 VRRP Standby Group Overview.............................................................................1-2

1.1.3 VRRP Timers ..........................................................................................................1-4

1.1.4 Format of VRRP Packets........................................................................................1-5

1.1.5 Principles of VRRP..................................................................................................1-7

1.1.6 VRRP Interface Tracking ........................................................................................1-7

1.1.7 VRRP Application (Taking IPv4-Based VRRP for Example)..................................1-7

1.2 Configuring VRRP for IPv4................................................................................................1-9

1.2.1 VRRP for IPv4 Configuration Task List...................................................................1-9

1.2.2 Enabling Users to Ping Virtual IP Addresses........................................................1-10

1.2.3 Configuring the Association Between Virtual IP Address and MAC Address.....................1-10

1.2.4 Creating Standby Group and Configuring Virtual IP Address...............................1-11

1.2.5 Configuring Standby Group Priority, Preemption Mode and Interface Tracking................. 1-12

1.2.6 Configuring VRRP Packet Attributes ....................................................................1-13

1.2.7 Displaying and Maintaining VRRP for IPv4...........................................................1-14

1.3 Configuring VRRP for IPv6..............................................................................................1-15

1.3.1 VRRP for IPv6 Configuration Task List.................................................................1-15

1.3.2 Enabling Users to Ping Virtual IPv6 Addresses.................................................... 1-15

1.3.3 Configuring the Association Between Virtual IPv6 Address and MAC Address................. 1-16

1.3.4 Creating Standby Group and Configuring Virtual IPv6 Address...........................1-17

1.3.5 Configuring Standby Group Priority, Preemption Mode and Interface Tracking................. 1-18

1.3.6 Configuring VRRP Packet Attributes ....................................................................1-19

1.3.7 Displaying and Maintaining VRRP for IPv6...........................................................1-20

1.4 IPv4-Based VRRP Configuration Examples....................................................................1-20

1.4.1 Single VRRP Standby Group Configuration Example ..........................................1-20

1.4.2 VRRP Interface Tracking Configuration Example.................................................1-23

1.4.3 Multiple VRRP Standby Group Configuration Example........................................1-26

1.5 IPv6-Based VRRP Configuration Examples....................................................................1-29

1.5.1 Single VRRP Standby Group Configuration Example ..........................................1-29

1.5.2 VRRP Interface Tracking Configuration Example.................................................1-32

1.5.3 Multiple VRRP Standby Group Configuration Example........................................1-36

1.6 Troubleshooting VRRP....................................................................................................1-39

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Chapter 1 VRRP Configuration

When configuring VRRP, go to these sections for information you are interested in:

z Introduction to VRRP

z Configuring VRRP for IPv4

z Configuring VRRP for IPv6

z IPv4-Based VRRP Configuration Examples

z IPv6-Based VRRP Configuration Examples

z Troubleshooting VRRP

 Note:

At present, the interfaces that VRRP involves can only be VLAN interfaces unless

otherwise specified.

1.1 Introduction to VRRP

1.1.1 VRRP Overview

Normally, as shown in Figure 1-1, you can configure a default route with the gateway as

the next hop for every host on a network segment, allowing all packets destined to the

other network segments to be sent over the default route to the gateway and then be

forwarded by the gateway. This enables hosts on a network segment to communicate

with external networks. However, when the gateway fails, all the hosts using the

gateway as the default next-hop switch fail to communicate with the external network.

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Gateway

Network

Host A

Host B

Host C

Figure 1-1 LAN networking

Apparently, this approach to enabling hosts on a network to communicate with external

networks is easy to configure but it imposes a very high requirement of performance

stability on the device acting as the gateway. A common way to improve system

reliability is to use more egress gateways, introducing the problem of routing among the

multiple egresses.

Virtual Router Redundancy Protocol (VRRP) is an error-tolerant protocol designed to

address this problem through separating physical devices from logical devices.

Deploying VRRP on multicast and broadcast LANs such as Ethernet, you can ensure

that the system can still provide highly reliable default links without changing

configurations (such as dynamic routing protocols, route discovery protocols) when a

device fails and prevent network interruption due to a single link failure.

There are two VRRP versions: VRRPv2 and VRRPv3. VRRPv2 is based on IPv4, while

VRRPv3 is based on IPv6. The two versions implement the same functions but provide

different commands.

1.1.2 VRRP Standby Group Overview

VRRP combines a group of switches (including a master and multiple backups) on a

LAN into a virtual router called standby group.

The VRRP standby group has the following features:

z A virtual router has an IP address. A host on the LAN only needs to know the IP

address of the virtual router and uses the IP address as the next hop of the default

route.

z Every host on the LAN communicates with external networks through the virtual

router.

z Switches in the standby group elect the gateway according to their priorities. Once

the master switch acting as the gateway fails, the other switches in the standby

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group elect a new gateway to undertake the responsibility of the failed switch, thus

ensuring that the hosts in the network segment can communicate with the external

networks uninterruptedly.

Host A

Host B

Host C

Switch A

Switch B

Switch C

Virtual router

Network

Figure 1-2 Network diagram for VRRP

As shown in

Figure 1-2, Switch A, Switch B, and Switch C form a virtual router, which

has its own IP address. Hosts on the Ethernet use the virtual router as the default

gateway.

The switch with the highest priority of the three switches is elected as the master switch

to act as the gateway, and the other two are backup switches.

Caution:

z The IP address of the virtual router can be either an unused IP address on the

segment where

z the standby group resides or the IP address of an interface on a switch in the

standby group. In the latter case, the switch is called the IP address owner.

z In a VRRP standby group, there can only be one IP address owner.

I. VRRP priority

VRRP determines the role (master or backup) of each switch in the standby group by

priority. A switch with a higher priority has more opportunity to become the master.

VRRP priority is in the range of 0 to 255. A bigger number means a higher priority.

Priorities 1 to 254 are configurable. Priority 0 is reserved for special uses and priority

255 for the IP address owner. When a switch acts as the IP address owner, its priority

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remains 255. That is, if there is an IP address owner in a standby group, it acts as the

master as long as it works properly.

II. Working mode

A switch in a standby group can work in one of the following two modes:

z Non-preemption mode

Once a switch in the standby group becomes the master, it stays as the master as long

as it operates normally, even if a backup switch is assigned a higher priority later.

z Preemption mode

Once a backup switch finds its priority higher than that of the switch acting as the

master, it sends VRRP advertisements to start a new master switch election in the

standby group and becomes the master. Accordingly, the original master switch

becomes a backup.

III. Authentication mode

VRRP provides two authentication modes:

z simple: Simple text authentication

You can adopt the simple text authentication mode in a network facing possible security

problems. A switch sending a packet fills the authentication key into the packet, and the

switch receiving the packet compares its local authentication key with that of the

received packet. If the two authentication keys are the same, the received VRRP

packet is considered real and valid; otherwise, the received packet is considered an

invalid one.

z md5: MD5 authentication

You can adopt MD5 authentication in a network facing severe security problems. The

switch encrypts a packet to be sent using the authentication key and MD5 algorithm

and saves the encrypted packet in the authentication header. The switch receiving the

packet uses the authentication key to decrypt the packet and checks whether the

packet is valid.

On a secure network, you need not set the authentication mode.

1.1.3 VRRP Timers

VRRP timers include VRRP advertisement interval timer and VRRP preemption delay

timer.

I. VRRP advertisement interval timer

The master switch in a VRRP standby group sends VRRP advertisements periodically

to inform the other switches in the standby group that it operates properly.

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You can adjust the interval of sending VRRP advertisements by setting the VRRP

advertisement interval timer. If a backup switch receives no advertisements in three

times the interval, the backup switch regards itself as the master switch and sends

VRRP advertisements to start a new master switch election.

II. VRRP preemption delay timer

In an unstable network, a backup switch may fail to receive the packets from the master

switch due to network congestion, thus causing the members in the group to change

their states frequently. This problem can be addressed through setting the VRRP

preemption delay timer.

With the VRRP preemption delay timer set, if a backup switch receives no

advertisement in three times the advertisement interval and then in preemption delay, it

considers that the master fails. In this case, it regards itself as the master and sends

VRRP advertisements to start a new master switch election in a standby group.

1.1.4 Format of VRRP Packets

VRRP uses multicast packets. The switch acting as the master sends VRRP packets

periodically to declare its existence. VRRP packets are also used for checking the

parameters of the virtual router and electing the master.

I. IPv4-based VRRP packet format

...

Version Type Virtual Rtr ID Priority Count IP Addrs

Auth Type Adver Int Checksum

IP address 1

IP address n

Authentication data 1

Authentication data 2

0 7 15 23 313

Figure 1-3 IPv4-based VRRP packet format

As shown in

Figure 1-3, an IPv4-based VRRP packet consists of the following fields:

z Version: Version number of the protocol, 2 for VRRPv2.

z Type: Type of the VRRP packet. Only one VRRP packet type is present, that is,

VRRP advertisement, which is represented by 1.

z Virtual Rtr ID (VRID): Number of the virtual router, that is, number of the standby

group. It ranges from 1 to 255.

z Priority: Priority of the switch in the standby group, in the range 0 to 255. A greater

value represents a higher priority.

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z Count IP Addrs: Number of virtual IP addresses for the standby group. A standby

group can have multiple virtual IP addresses.

z Auth Type: Authentication type. 0 means no authentication, 1 means simple

authentication, and 2 means MD5 authentication.

z Adver Int: Interval for sending advertisement packets, in seconds. The default is 1.

z Checksum: 16-bit checksum for validating the data in VRRP packets.

z IP Address: Virtual IP address entry of the standby group. The allowed number is

given by the Count IP Addrs field.

z Authentication Data: Authentication key. Currently, this field is used only for simple

authentication and is 0 for any other authentication modes.

II. IPv6-based VRRP packet format

Version Type Virtual Rtr ID Priority Count IPv6 Addrs

Auth Type Adver Int Checksum

IPv6 address 1

Authentication data 1

Authentication data 2

IPv6 address n

0 7 15 23 313

Figure 1-4 IPv6-based VRRP packet format

As shown in

Figure 1-4, an IPv6-based VRRP packet consists of the following fields:

z Version: Version number of the protocol, 3 for VRRPv3.

z Type: Type of the VRRP packet. Only one VRRP packet type is present, that is,

VRRP advertisement, which is represented by 1.

z Virtual Rtr ID (VRID): Number of the virtual router, that is, number of the standby

group. It ranges from 1 to 255.

z Priority: Priority of the switch in the standby group, in the range 0 to 255. A greater

value represents a higher priority.

z Count IPv6 Addrs: Number of virtual IPv6 addresses for the standby group. A

standby group can have multiple virtual IPv6 addresses.

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z Auth Type: Authentication type. 0 means no authentication, 1 means simple

authentication. VRRPv3 does not support MD5 authentication.

z Adver Int: Interval for sending advertisement packets, in centiseconds. The default

is 100.

z Checksum: 16-bit checksum for validating the data in VRRPv3 packets.

z IPv6 Address: Virtual IPv6 address entry of the standby group. The allowed

number is given by the Count IPv6 Addrs field.

z Authentication Data: Authentication key. Currently, this field is used only for simple

authentication and is 0 for any other authentication modes.

1.1.5 Principles of VRRP

z With VRRP enabled, the switches determine their respective roles in the standby

group by priority. The switch with the highest priority becomes the master, while

the others are the backups. The master sends VRRP advertisement packets

periodically to notify the backups that it is working properly, and each of the

backups starts a timer to wait for advertisement packets from the master.

z In preemption mode, when a backup receives a VRRP advertisement packet, it

compares the priority in the packet with that of its own. If its priority is higher, it

becomes the master; otherwise, it remains a backup.

z In non-preemption mode, the switch in the standby group remains as a master or

backup as long as the master does not fail. The backup will no become the master

even if the former is configured with a higher priority.

z If the timer of a backup expires but the backup still does not receive any VRRP

advertisement packet, it considers that the master fails. In this case, the backup

switch considers itself as the master switch and sends VRRP advertisements to

start the election process to elect a new master switch for forwarding packets.

1.1.6 VRRP Interface Tracking

The interface tracking function expands the backup functionality of VRRP. It provides

backup not only when the interface to which a standby group is assigned fails but also

when other interfaces on the switch become unavailable. This is achieved by tracking

interfaces. When a monitored interface goes down, the priority of the switch owning the

interface is automatically decreased by a specified value, allowing a higher priority

switch in the standby group to become the master.

1.1.7 VRRP Application (Taking IPv4-Based VRRP for Example)

I. Master/backup

In master/backup mode, only one switch, the master, provides services. When the

master fails, a new master is elected from the original backups. This mode requires

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only one standby group, in which each switch holds different priorities and the one with

the highest priority becomes the master, as shown in

Figure 1-5.

Figure 1-5 VRRP in master/backup mode

At the beginning, Switch A is the master and therefore can forward packets to external

networks, while Switch B and Switch C are backups and are thus in the state of

listening. If Switch A fails, Switch B and Switch C will elect for the new master. The new

master takes over the forwarding task to provide services to hosts on the LAN.

II. Load balancing

You can create more than one standby group on an interface of a switch, allowing the

switch to be the master of one standby group but a backup of another at the same time.

In load balancing mode, multiple switches provide services at the same time. This

mode requires two or more standby groups, each of which includes a master and one

or more backups. The masters of the standby groups can be assumed by different

switches, as shown in

Figure 1-6.

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Host A

Host B

Host C

Switch A

Backup

Switch B

Backup

Switch C

Master

Virtual router 2

Virtual router 3Virtual router 1

Master

Backup

Backup Backup

Master

Backup

Network

Figure 1-6 VRRP in load balancing mode

A switch can be in multiple standby groups and hold a different priority in different

group.

Figure 1-6, three standby groups are present:

z Standby group 1: Switch A is the master; Switch B and Switch C are the backups.

z Standby group 2: Switch B is the master; Switch A and Switch C are the backups.

z Standby group 3: Switch C is the master; Switch A and Switch B are the backups.

For load balancing among Switch A, Switch B, and Switch C, hosts on the LAN need to

be configured to use standby group 1, 2, and 3 as the default gateways respectively.

When configuring VRRP priorities, ensure that each switch holds such a priority in each

standby group that it will take the expected role in the group.

1.2 Configuring VRRP for IPv4

1.2.1 VRRP for IPv4 Configuration Task List

Complete these tasks to configure VRRP for IPv4:

Task Remarks

Enabling Users to Ping Virtual IP Addresses Optional

Configuring the Association Between Virtual IP Address and

MAC Address

Optional

Creating Standby Group and Configuring Virtual IP Address Required

Configuring Standby Group Priority, Preemption Mode and

Interface Tracking

Optional

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Task Remarks

Configuring VRRP Packet Attributes Optional

1.2.2 Enabling Users to Ping Virtual IP Addresses

You can configure whether the master switch responds to the received ICMP echo

requests, that is, whether the virtual IP address of a standby group can be successfully

pinged.

Follow these steps to enable a user to successfully ping the virtual IP addresses of

standby groups:

To do… Use the command… Remarks

Enter system view

system-view

—

Enable users to ping

virtual IP address of the

standby group

vrrp ping-enable

Optional

Enabled by default.

Caution:

Configure this function before creating a standby group. Otherwise, your configuration

will fail.

1.2.3 Configuring the Association Between Virtual IP Address and MAC Address

After the virtual IP address of a standup group is associated with a MAC address, the

master switch takes the configured MAC address as the source MAC address of the

packets to be sent, so that the hosts in the internal network can learn the association

between the IP address and the MAC address and thus forward the packets to be

forwarded to the other network segments to the master switch properly.

There are two types of association between virtual IP address and MAC address:

z Virtual IP address is associated with virtual router MAC address

By default, a MAC address is created for a standby group after the standby group is

created, and the virtual IP address is associated with the virtual MAC address. With

such association adopted, the hosts in the internal network need not update the

association between IP address and MAC address when the master switch changes.

z Virtual IP address is associated with real MAC address of the interface

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When an IP address owner exists in a standby group, if you associate the virtual IP

address with the virtual MAC address, two MAC addresses are associated with an IP

address. In this case, you can associate the virtual IP address of the standby group with

the real MAC address, so that the packets from a host are forwarded to the IP address

owner according the real MAC address.

Follow these steps to configure the association between MAC address and virtual IP

address:

To do… Use the command… Remarks

Enter system view

system-view

—

Configure the association

between virtual IP

address and MAC

address

vrrp method { real-mac |

virtual-mac }

Optional

The virtual MAC address

is associated with the

virtual IP address by

default.

Caution:

You should configure this function before creating a standby group. Otherwise, you

cannot modify the mapping between the virtual IP address and the MAC address.

1.2.4 Creating Standby Group and Configuring Virtual IP Address

You need to configure a virtual IP address for a standby group when creating the

standby group. A VRRP standby group is created automatically when you specify the

first virtual IP address for the standby group. If you specify a virtual IP address for the

standby group later, the virtual IP address is only added to the virtual IP address list of

the VRRP standby group.

I. Configuration prerequisites

Before creating standby group and configuring virtual IP address, you should first

configure the IP address of the interface and ensure that the virtual IP address to be

configured is in the same network segment as the IP address of the interface.

II. Configuration procedure

Follow these steps to create standby group and configure virtual IP address:

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To do… Use the command… Remarks

Enter system view

system-view

—

Enter the specified

interface view

interface interface-type

interface-number

—

Create standby group and

configure virtual IP

address of the standby

group

vrrp vrid virtual-router-id

virtual-ip virtual-address

Required

Standup group is not

created by default.

Caution:

z The maximum number of standby groups on an interface and the maximum number

of virtual IP addresses in a standby group vary by device.

z A standby group is removed after you remove all the virtual IP addresses in it. In

addition, configurations on that standby group no longer take effect.

z The virtual IP address of the virtual router can be either an unused IP address on the

segment where the standby group resides or the IP address of an interface on a

switch in the standby group. In the latter case, the switch is called the IP address

owner.

z The virtual IP address of the standby group cannot be 0.0.0.0, 255.255.255.255,

loopback address, non A/B/C address and other illegal IP addresses such as

0.0.0.1.

z Only when the configured virtual IP address and the interface IP address belong to

the same segment and are legal host addresses can the standby group operate

normally. If the configured virtual IP address and the interface IP address do not

belong to the same network segment, or the configured IP address is the network

address or network broadcast address of the network segment that the interface IP

address belongs to, the state of the standby group is always initialize though you

can perform the configuration successfully, that is, VRRP does not take effect in this

case.

1.2.5 Configuring Standby Group Priority, Preemption Mode and Interface Tracking

I. Configuration prerequisites

Before you configure these features, you should first create a standby group on the

interface and configure virtual IP address for it.

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II. Configuration procedure

By configuring switch priority, preemption mode and interface tracking, you can decide

which switch in the standby group serves as the Master.

Follow these steps to configure standby group priority, preemption mode and interface

tracking:

To do… Use the command… Remarks

Enter system view

system-view

—

Enter interface view

interface interface-type

interface-number

—

Configure switch priority

in the standby group

vrrp vrid virtual-router-id

priority priority-value

Optional

100 by default.

Configure the switch in

the standby group to work

in preemption mode and

configure preemption

delay

vrrp vrid virtual-router-id

preempt-mode [ timer

delay delay-value ]

Optional

The switch in the standby

group works in

preemption mode and the

preemption delay is 0

seconds by default.

Configure the interface to

be tracked

vrrp vrid virtual-router-id

track interface

interface-type

interface-number

[ reduced

priority-reduced ]

Optional

No interface is being

tracked by default.

Caution:

z The priority of an IP address owner is always 255 and not configurable.

z Interface tracking is not configurable to an IP address owner.

z The priority of a device is restored if the state of the interface under tracking

changes from down to up.

1.2.6 Configuring VRRP Packet Attributes

I. Configuration prerequisites

Before configuring the relevant attributes of VRRP packets, you should first create the

standby group and configure the virtual IP address.

II. Configuration procedure

Follow these steps to configure VRRP packet attributes:

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To do… Use the command… Remarks

Enter system view

system-view

—

Enter the specified

interface view

interface interface-type

interface-number

—

Configure the

authentication mode and

authentication key when

the standby groups send

and receive VRRP

packets

vrrp vrid virtual-router-id

authentication-mode

{ md5 | simple } key

Optional

Authentication is not

performed by default

Configure the time interval

for the Master in the

standby group to send

VRRP advertisement

vrrp vrid virtual-router-id

timer advertise

adver-interval

Optional

1 second by default

Disable TTL check on

VRRP packets

vrrp un-check ttl

Optional

Enabled by default

Do not create a standby

group before executing

this command.

 Note:

z You may configure different authentication modes and authentication keys for the

standby groups on an interface. However, the members of the same standby group

must use the same authentication mode and authentication key.

z Factors like excessive traffic or different timer setting on switches can cause the

Backup timer to time-out abnormally and trigger a change of the state. To solve this

problem, you can prolong the time interval to send VRRP packets and configure a

preemption delay.

1.2.7 Displaying and Maintaining VRRP for IPv4

To do… Use the command… Remarks

Display VRRP status

display vrrp [ verbose ]

[ interface interface-type

interface-number [ vrid

virtual-router-id ] ]

Available in any view

Display VRRP statistics

display vrrp statistics

[ interface interface-type

interface-number [ vrid

virtual-router-id ] ]

Available in any view

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To do… Use the command… Remarks

Remove VRRP statistics

reset vrrp statistics

[ interface interface-type

interface-number [ vrid

virtual-router-id ] ]

Available in user view

1.3 Configuring VRRP for IPv6

1.3.1 VRRP for IPv6 Configuration Task List

Complete these tasks to configure VRRP for IPv6:

Task Remarks

Enabling Users to Ping Virtual IPv6 Addresses Optional

Configuring the Association Between Virtual IPv6 Address and

MAC Address

Optional

Creating Standby Group and Configuring Virtual IPv6 Address Required

Configuring Standby Group Priority, Preemption Mode and

Interface Tracking

Optional

Configuring VRRP Packet Attributes Optional

1.3.2 Enabling Users to Ping Virtual IPv6 Addresses

You can configure whether the master switch responds to the received ICMPv6 echo

requests, that is, whether the virtual IPv6 address of a standby group can be pinged

through.

Follow these steps to enable a user to successfully ping the virtual IPv6 addresses of

standby groups:

To do... Use the command... Remarks

Enter system view

system-view

—

Enable a user to ping

virtual IPv6 address of the

standby group

vrrp ipv6 ping-enable

Optional

Enabled by default

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Caution:

You should configure this function before creating a standby group. Otherwise, you

cannot ping the virtual IPv6 addresses of standby groups.

1.3.3 Configuring the Association Between Virtual IPv6 Address and MAC Address

After the virtual IPv6 address of a standup group is associated with the MAC address,

the master switch takes the configured MAC address as the source MAC address of the

packets to be sent, so that the hosts in the internal network can learn the association

between the IPv6 address and the MAC address and thus forward the packets to be

forwarded to the other network segments to the master switch properly.

There are two types of association between virtual IPv6 address and MAC address:

z Virtual IPv6 address is associated with virtual router MAC address

By default, a MAC address is created for a standby group after the standby group is

created, and the virtual IPv6 address is associated with the virtual MAC address. With

such association adopted, the hosts in the internal network need not update the

association between IPv6 address and MAC address when the master switch changes.

z Virtual IPv6 address is associated with real MAC address of the interface

When an IP address owner exists in a standby group, if you associate the virtual IPv6

address with the virtual MAC address, two MAC addresses are associated with an IPv6

address. In this case, you can associate the virtual IPv6 address of the standby group

with the real MAC address, so that the packets from a host is forwarded to the IP

address owner according the real MAC address.

Follow these steps to configure the association between MAC address and virtual IPv6

address:

To do… Use the command… Remarks

Enter system view

system-view

—

Configure the association

between virtual IPv6

address and MAC

address

vrrp ipv6 method

{ real-mac | virtual-mac }

Optional

The virtual MAC address

of the standby group is

associated with the virtual

IPv6 address by default.

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Caution:

You should configure this function before creating a standby group. Otherwise, you

cannot modify the mapping between the virtual IPv6 address and the MAC address.

1.3.4 Creating Standby Group and Configuring Virtual IPv6 Address

You need to configure a virtual IPv6 address for a standby group when creating the

standby group. A VRRP standby group is created automatically when you specify the

first virtual IPv6 address for the standby group. If you specify a virtual IPv6 address for

the standby group later, the virtual IPv6 address is only added to the virtual IPv6

address list of the VRRP standby group.

I. Configuration prerequisites

Before creating standby group and configuring virtual IPv6 address, you should first

configure the IPv6 address of the interface and ensure that the virtual IPv6 address to

be configured is in the same network segment as the IPv6 address of the interface.

II. Configuration procedure

Follow these steps to create standby group and configure its virtual IPv6 address:

To do… Use the command… Remarks

Enter system view

system-view

—

Enter the specified

interface view

interface interface-type

interface-number

—

Create standby group and

configure its virtual IPv6

address

vrrp ipv6 vrid

virtual-router-id virtual-ip

virtual-address

[ link-local ]

Required

No standby group is

created by default.

The first virtual IPv6

address of the standby

group must be a link local

address. Only one link

local address is allowed in

a standby group, and

must be removed the last.

Operation Manual – VRRP

H3C S5500-EI Series Ethernet Switches Chapter 1 VRRP Configuration

1-18

Caution:

z The maximum number of standby groups on an interface and the maximum number

of virtual IPv6 addresses in a standby group vary by device.

z A standby group is removed after you remove all the virtual IPv6 addresses in it. In

addition, configurations on that standby group no longer take effect.

1.3.5 Configuring Standby Group Priority, Preemption Mode and Interface Tracking

I. Configuration prerequisites

Before configuring these features, you should first create the standby group and

configure the virtual IPv6 address.

II. Configuration procedure

By configuring standby group priority, preemption mode and interface tracking, you can

decide which switch in the standby group serves as the Master.

Follow these steps to configure standby group priority, preemption mode and interface

tracking:

To do… Use the command… Remarks

Enter system view

system-view

—

Enter the specified

interface view

interface interface-type

interface-number

—

Configure the priority of

the switch in the standby

group

vrrp ipv6 vrid

virtual-router-id priority

priority-value

Optional

100 by default

Configure the switch in

the standby to work in

preemption mode and

configure preemption

delay of the standby

group

vrrp ipv6 vrid

virtual-router-id

preempt-mode [ timer

delay delay-value ]

Optional

The switch in the standby

group works in

preemption mode and the

preemption delay is zero

seconds by default.

Configure the interface to

be tracked

vrrp ipv6 vrid

virtual-router-id track

interface interface-type

interface-number

[ reduced

priority-reduced ]

Optional

No interface is being

tracked by default.

Operation Manual – VRRP

H3C S5500-EI Series Ethernet Switches Chapter 1 VRRP Configuration

1-19

Caution:

z The priority of an IP address owner is always 255 and not configurable.

z Interface tracking is not configurable on an IP address owner.

z The priority of a device is reset if the state of the interface under tracking changes

from down to up.

1.3.6 Configuring VRRP Packet Attributes

I. Configuration prerequisites

Before configuring the relevant attributes of VRRP packets, you should first create the

standby group and configure the virtual IPv6 address.

II. Configuration procedure

Follow these steps to configure VRRP packet attributes:

To do… Use the command… Remarks

Enter system view

system-view

—

Enter the specified

interface view

interface interface-type

interface-number

—

Configure the

authentication mode and

authentication key when

the standby groups send

and transmit VRRP

packets

vrrp ipv6 vrid

virtual-router-id

authentication-mode

simple key

Optional

Authentication is not

performed by default

Configure the time interval

for the Master in the

standby group to send

VRRP advertisement

vrrp ipv6 vrid

virtual-router-id timer

advertise adver-interval

Optional

100 centiseconds by

default

You may configure different authentication modes and authentication keys for the

standby groups on an interface. However, the members of the same standby group

must use the same authentication mode and authentication key.

Factors like excessive traffic or different timer setting on switches can cause the

Backup timer to time-out abnormally and change the state. To solve this problem, you

can prolong the time interval to send VRRP packets and configure a delay for

preemption.

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H3C S5500-EI Series Operating instructions

Brand: H3C

Model: S5500-EI Series

Category: Network switches

Type: Operating instructions

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H3C S5500-EI Series Operating instructions

H3C S5500-EI Series Operating instructions

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