VRRP and VARP
A virtual IP (VIP) address is an IP address that does not directly connect to a specific interface. Inbound packets sent to a Virtual IP address are redirected to a physical network interface. VIPs support connection redundancy by assigning the address to multiple switches. If one device becomes unavailable, packets sent to the address are still serviced by the functioning device.
Arista switches support virtual IP addresses through Virtual Router Redundancy Protocol, version 2 (VRRPv2), Virtual Router Redundancy Protocol, version 3 (VRRPv3), and Virtual-ARP (VARP). This chapter describes the Arista switch support of virtual IP addresses and contains these sections:
VRRP and VARP Conceptual Overview
VRRPv2
A virtual router, also known as a virtual router group, is defined by a Virtual Router Identifier (VRID) and a virtual IP address. A virtual routers mapping of VRID and IP address must be consistent among all switches implementing the virtual router group. A virtual routers scope is restricted to a single LAN.
A LAN may contain multiple virtual routers for distributing traffic. Each virtual router on a LAN is assigned a unique VRID. A switch may be configured with virtual routers among multiple LANs.
VRRP uses priority ratings to assign Master or Backup roles for each VRRP router configured for a virtual router group. The Master router sends periodic VRRP Advertisement messages along the LAN and forwards packets received by the virtual router to their destination. Backup routers are inactive but are available to assume Master router duties when the current Master fails.
A VRRP can be configured to allow VRRP routers with higher priority to take over Master router duties. Alternatively, the group can be configured to prevent a router from preemptively assuming the Master role. A VRRP router is always assigned the Master of any virtual router configured with the address owned by the VRRP router, regardless of the preemption prevention setting.
On 7280R3, 7500R3 and 7800R3 series, maximally 14 unique VRRP groups can be configured along with VARP and MLAG Peer gateway virtual MAC capabilities.
VRRPv3
RFC 5798 defines version 3 of the Virtual Router Redundancy Protocol (VRRP) for both IPv4 and IPv6. It is based on version 2 of VRRP, as defined in RFC 3768.
VARP
Virtual VRRP (VARP) allows multiple switches to simultaneously route packets from a common IP address in an active-active router configuration. Each switch is configured with the same set of virtual IP addresses on corresponding VLAN interfaces and a common virtual MAC address. In MLAG configurations, VARP is preferred over VRRP because VARP does not require traffic to traverse the peer-link to the master router as VRRP would.
A maximum of 500 virtual IP addresses can be assigned to a VLAN interface. All virtual addresses on all VLAN interfaces resolve to the same virtual MAC address.
VARP functions by having each switch respond to ARP and GARP requests for the configured router IP address with the virtual MAC address. The virtual MAC address is only for inbound packets and never used in the source field of outbound packets.
When ip routing is enabled, packets to the virtual MAC address are routed to the next hop destination.
VRRP and VARP Implementation procedures
VRRP configuration for IPv4
To implement a virtual router, it must be configured and enabled. A virtual router is typically configured before it is enabled; this ensures that the VRRP router operates as required before its priority settings immediately make it the master virtual router. Because assigning a primary address to a virtual router enables it, address assignment is normally performed after all other configuration tasks.
The no vrrp command removes all VRRP commands for the specified virtual router from running-config.
Virtual Router configuration
- VRRP version (default = version 2)
- Router priority (default = 100)
- Preemption option (default is enabled)
- Advertisement timer (default = one second)
- Description (optional parameter)
- Peer authentication (optional parameter)
- Secondary IP addresses (optional parameter)
VRRP Version
The vrrp ipv4 version command sets the version of VRRP for the corresponding IPv4 virtual router. IPv6 version is not configurable as it only supports version 3. The version selected in a VRRP group can either be same for all group members or independent of each other. By default, Arista switches use VRRP version 2, which supports only IPv4 environments. VRRP version 3 supports both IPv4 and IPv6 environments.
Example
switch(config)# interface vlan 20
switch(config-if-vl20)# vrrp 1 ipv4 version 3
switch(config-if-vl20)#Master and Backup Router
The VRRP routers within a virtual router group determine the Master router through priority settings. Priority values range from 254 (highest priority) to 1 (lowest priority). Priority is either set by a CLI command or is assigned the default value of 100. A switch specifies priority settings for each of its virtual routers. Once set, VRRP priority level can also be changed by a tracked object. The vrrp tracked-object command configures the VRRP client process to track an object created by the track command and react if its status changes to down.
Preemption mode determines when a VRRP router with a higher priority rating becomes the Master router. If preemption is enabled, the VRRP router with the highest priority immediately becomes the Master router. If preemption is disabled, a VRRP router with a higher priority value does not become the Master router unless the current Master becomes unavailable; this is applicable when a new VRRP router becomes available on the LAN or VRRP routers priority value changes for the virtual router.
The vrrp priority-level command configures the switchs priority setting for the specified virtual router.
Example
switch(config-if-vl20)# vrrp 15 priority-level 250
switch(config-if-vl20)#The vrrp preempt command controls the preempt mode setting of the specified virtual router. By default, preempt mode is enabled.
Examples
- This command disables preempt mode for the virtual router
15 on vlan
20.
switch(config-if-vl20)# no vrrp 15 preempt switch(config-if-vl20)# - This command enables preempt mode for the virtual router
30 on vlan
20.
switch(config-if-vl20)#vrrp 30 preempt switch(config-if-vl20)#
The vrrp preempt delay command configures a period between an event that elevates a switch to master VRRP router status and the switch's assumption of master VRRP router role. Command options configure delays during normal operation and after a switch reboot.
Advertisement Interval
The Master router sends periodic VRRP Advertisement messages to other VRRP routers. The vrrp advertisement interval command specifies the interval between successive advertisement message transmissions.
The advertisement interval also defines the timeout that determines when the switch assumes the Master router role. This timeout interval is three times the advertisement interval.
Example
switch(config-if-vl100)# vrrp 35 advertisement interval 10
switch(config-if-vl100)#Description
The vrrp session description command associates a text string to the specified virtual router. The maximum string length is 80 characters. The string has no functional impact on the virtual router.
Example
switch(config-if-vl20)# vrrp 15 session description Laboratory Router
switch(config-if-vl20)#Peer Authentication
VRRP peer authentication validates VRRP advertisement packets that the switch receives from other VRRP routers in a specified virtual router group. When a virtual router uses authentication, all VRRP routers in the group must use the same authentication parameters.
The vrrp peer authentication command configures virtual router authentication parameters for the specified virtual router.
Example
switch(config-if-vl100)#vrrp 40 peer authentication text 12345
switch(config-if-vl100)#Secondary Addresses
The vrrp ipv4 secondary command assigns a secondary IP address to a virtual router. Secondary addresses are optional; a virtual routers configuration may include more than one secondary address command. The primary and secondary address list must be identical for all switches in a virtual router group.
A primary IP address is assigned to a virtual router with the vrrp ipv4 command (Virtual Router Enabling and the Primary IP address).
Example
switch(config-if-vl20)# vrrp 15 ipv4 10.2.4.5 secondary
switch(config-if-vl20)#Virtual Router Enabling and the Primary IP address
The vrrp ipv4 command configures the primary IP address of the specified virtual router and enables the virtual router if the primary address is contained within the configuration mode interfaces IP address subnet. A virtual routers configuration may contain only one primary IP address assignment command; subsequent vrrp ipv4 commands reassign the virtual routers primary IP address.
Example
switch(config-if-vl20)# vrrp 15 ipv4 10.1.1.5
switch(config-if-vl20)#Disabling VRRP
The vrrp disabled command places the switch in stopped state for the specified virtual router. While in stopped state, the switch cannot act as a Master or backup router for the virtual router group. The no vrrp disabled command changes the switchs virtual router state to backup or master if the virtual router is properly configured.
- This command places the switch in stopped mode
for virtual router 24 on vlan
20.
switch(config-if-vl20)# vrrp 24 disabled switch(config-if-vl20)# - This command moves the switch out of stopped
mode for virtual router 24 on vlan
20.
switch(config-if-vl20)# no vrrp 24 disabled switch(config-if-vl20)# - This command configures the switch to enter
stopped mode for virtual router 24 on vlan
20 if the status of tracked-object
interfaceE6/48 changes to
down.
switch(config-if-vl20)# vrrp 24 tracked-object interfaceE6/48 shutdown switch(config-if-vl20)#
The no vrrp and no vrrp ipv4 commands delete the specified virtual IP address from the interface. Additionally, the no vrrp command removes all residual VRRP commands for the virtual router.
- This command removes all VRRP configuration
commands for virtual router 10 on vlan
15.
switch(config-if-vl15)# no vrrp 10 switch(config-if-vl15)# - This command disables virtual router
25 on vlan20 and removes the
primary IP address from its
configuration.
switch(config-if-vl20)# no vrrp 25 ipv4 10.1.1.5 switch(config-if-vl20)#
VRRP configuration for IPv6
To implement a virtual router, it must be configured and enabled. A virtual router is typically configured before it is enabled; this ensures that the VRRP router operates as required before its priority settings immediately make it the master virtual router. Because assigning a primary address to a virtual router enables it, address assignment is normally performed after all other configuration tasks.
The no vrrp command removes all VRRP commands for the specified virtual router from running-config.
Configuring VRRP for IPv6
Specify the VRRP Version
The vrrp ipv4 version command sets the version of VRRP used on an interface. The version selected in a VRRP group must be the same for all group members. By default, Arista switches use VRRP version 2, which is not compatible with IPv6.
Example
switch(config)# interface vlan 20
switch(config-if-vl20)# vrrp 1 ipv4 version 3
switch(config-if-vl20)#Create a VRRP Group and Configure a Virtual IPv6 Address
The vrrp ipv6 command assigns an IPv6 address to the interface being configured and creates a VRRP group.
Example
switch(config)# interface vlan 20
switch(config-if-vl20)# vrrp 3 ipv6 2001:db8:0:1::1
switch(config-if-vl20)#Configure Tracking
The vrrp tracked-object command configures the VRRP client process to track an object created by the track command and react if its status changes to down.
Example
switch(config-if-vl20)# vrrp 1 tracked-object ETH8 shutdown
switch(config-if-vl20)#Configure the Priority Level
The vrrp priority-level command configures the switchs priority setting for the specified virtual router.
Example
switch(config-if-vl20)# vrrp 15 priority-level 250
switch(config-if-vl20)#Configure the Preemption Mode
Preemption mode determines when a VRRP router with a higher priority rating becomes the Master router. If preemption is enabled, the VRRP router with the highest priority immediately becomes the Master router. If preemption is disabled, a VRRP router with a higher priority value does not become the Master router unless the current Master becomes unavailable; this is applicable when a new VRRP router becomes available on the LAN or VRRP routers priority value changes for the virtual router.
The vrrp preempt command controls the preempt mode setting of the specified virtual router. By default, preempt mode is enabled.
Example
switch(config-if-vl20)# vrrp 30 preemptConfigure the VRRP Advertisement Interval
The ip virtual-router mac-address advertisement-interval command specifies the interval between advertisement packets sent by the master router to the VRRP group members.
Example
switch(config)# interface vlan 20
switch(config-if-vl20)# ip virtual-router mac-address advertisement-interval 60
switch(config-if-vl20)#Verify VRRP IPv6 configurations
Use the following commands to display the VRRP configurations and status.
Show VRRP Group
The show vrrp command displays information about the Virtual Router Redundancy Protocol (VRRP) groups configured on a specified interface.
Example
switch# show vrrp interface vlan 3060 brief
Interface Id Ver Pri Time State VrIps
Vlan3060 1 3 100 3609 Master 2001::2
2001::3
Vlan3060 2 3 100 3609 Master 2002::2
2002::3
switch#VARP configuration
Implementing VARP consists of assigning virtual IP addresses to VLAN interfaces and configuring a virtual MAC address.
Virtual IP Addresses
The ip virtual-router address command assigns a virtual IP address to the VLAN interface being configured. Unlike VRRP, the virtual IP address does not have to be in the same subnet as the physical interface.
A virtual IPv4 address may optionally be configured with a subnet, but doing so modifies the behavior of ARP requests sent from the router. When the router sends an ARP request for an IPv4 address in a virtual subnet, the ARP request uses the virtual IPv4 address as the source IP address and the virtual MAC address as the source MAC address inside the ARP header. For virtual IP addresses configured without the subnet option, no modifications are made to outgoing ARP requests.
- These commands configure a Switch Virtual Interface (SVI) and a virtual IP address for
VLAN
10.
switch(config)# interface vlan 10 switch(config-if-Vl10)# ip address 10.0.0.2/24 switch(config-if-Vl10)# ip virtual-router address 10.0.0.6 switch(config-if-Vl10)# ipv6 address 2001::1/64 switch(config-if-Vl10)# ipv6 virtual-router address 2001::2 switch(config-if-Vl10)# exit switch(config)# - These commands configure a Switch Virtual Interface (SVI) and a virtual IPv4 address
with a subnet for vlan 10. A static route is added to indicate
that the virtual subnet is reachable through vlan
10.
switch(config)# ip route 192.0.0.0/24 vlan 10 switch(config)# interface vlan 10 switch(config-if-Vl10)# ip address 10.0.0.2/24 switch(config-if-Vl10)# ip virtual-router address 192.0.0.6/24 switch(config-if-Vl10)# exit switch(config)#
Virtual MAC Address
The ip virtual-router mac-address command assigns a virtual MAC address to the switch. The switch maps all virtual router IP addresses to this MAC address. The address is receive-only; the switch never sends packets with this address as the source.
When the destination MAC of a packet destined to a remote network matches the virtual MAC address, the MLAG peer forwards the traffic to the next hop destination. Each MLAG peer must have the same routes available, either through static configuration or learned through a dynamic routing protocol.
Example
switch(config)# ip virtual-router mac-address 001c.7300.0099
switch(config)#Show Virtual MAC Address
To display the virtual router MAC and IP addresses, enter the show ip virtual-router command.
Example
switch# show ip virtual-router
IP virtual router is configured with MAC address: 24cd.5a29.cc31
Interface IP Address Virtual IP Address Status Protocol
Vlan15 10.1.1.3/24 10.1.1.15 up up
Vlan15 10.1.1.3/24 10.1.1.16 up up
Vlan15 10.1.1.3/24 10.1.1.17 up up
Vlan20 10.12.1.6/24 10.1.1.51 up up
Vlan20 10.12.1.6/24 10.1.1.53 up up
Vlan20 10.12.1.6/24 10.1.1.55 up up
switch#Show IPv6 Virtual-Router
The show ipv6 virtual-router command displays the virtual MAC address assigned to the switch and all virtual IPv6 addresses assigned to each VLAN interface.
Example
switch# show ipv6 virtual-router
IP virtual router is configured with MAC address: 001c.7300.0099
MAC address advertisement interval: 30 seconds
Interface Vlan4094
State is up
Protocol is up
IPv6 address
2001:b8:2001::1011/64
Virtual IPv6 address
2001:db8:ac10:fe01::
switch#VRRP and VARP Implementation Examples
VRRP Examples
- Example 1 configures two switches in a single virtual router group. This implementation protects the LAN against the failure of one router.
- Example 2 configures two switches into two virtual routers within a single LAN. This implementation protects the LAN against the failure of one router and balances traffic between the routers.
- Example 3 configures three switches to implement virtual routers on two LANs. Each LAN contains two virtual routers. One switch is configured into four virtual routers – two on each LAN.
VRRP Example 1: One Virtual Router on One LAN
The network diagram displays the Example 1 network. Two switches are configured as VRRP routers to form one virtual router.
The following code configures the first switch (Router A) as the master router and the second switch (Router B) as a backup router for virtual router 10 on vlan 50. Router A becomes the Master virtual router by setting its priority at 200; Router B maintains the default priority of 100. The advertisement interval is three seconds on both switches. Priority preemption is enabled by default.
Switch Code that Implements Router A on the First Switch
switch-A(config)# interface vlan 50
switch-A(config-if-vl50)# ip address 10.10.4.1/24
switch-A(config-if-vl50)# no vrrp 10
switch-A(config-if-vl50)# vrrp 10 priority 200
switch-A(config-if-vl50)# vrrp 10 advertisement interval 3
switch-A(config-if-vl50)# vrrp 10 ip 10.10.4.10
switch-A(config-if-vl50)# exitSwitch Code that Implements Router B on the Second Switch
switch-B(config)# interface vlan 50
switch-B(config-if-vl50)# ip address 10.10.4.2/24
switch-B(config-if-vl50)# no vrrp 10
switch-B(config-if-vl50)# vrrp 10 advertisement interval 3
switch-B(config-if-vl50)# vrrp 10 ip 10.10.4.10
switch-B(config-if-vl50)# exitVRRP Example 2: Two Virtual Routers on One LAN
The nnetwork diagram displays Example 2. Two switches are configured as VRRP routers to form two virtual routers on one LAN. Using two virtual routers distributes the LAN traffic between the switches.
- Router A is the master for virtual router 10 and backup for virtual router 20.
- Router B is the master for virtual router 20 and backup for virtual router 10.
- VRRP advertisement interval is 3 seconds on virtual router 10 and 5 seconds on virtual router 20.
- Priority preemption is enabled by default for both virtual routers.
Switch Code that Implements Router A on the First Switch
switch-A(config)# interface vlan 50
switch-A(config-if-vl50)# ip address 10.10.4.1/24
switch-A(config-if-vl50)# no vrrp 10
switch-A(config-if-vl50)# vrrp 10 priority 200
switch-A(config-if-vl50)# vrrp 10 advertisement interval 3
switch-A(config-if-vl50)# vrrp 10 ip 10.10.4.10
switch-A(config-if-vl50)# no vrrp 20
switch-A(config-if-vl50)# vrrp 20 advertisement interval 5
switch-A(config-if-vl50)# vrrp 20 ip 10.10.4.20
switch-A(config-if-vl50)# exitSwitch Code that Implements Router B on the Second Switch
switch-B(config)# interface vlan 50
switch-B(config-if-vl50)# ip address 10.10.4.2/24
switch-B(config-if-vl50)# no vrrp 10
switch-B(config-if-vl50)# vrrp 10 advertisement interval 3
switch-B(config-if-vl50)# vrrp 10 ip 10.10.4.10
switch-B(config-if-vl50)# no vrrp 20
switch-B(config-if-vl50)# vrrp 20 priority 200
switch-B(config-if-vl50)# vrrp 20 advertisement interval 5
switch-B(config-if-vl50)# vrrp 20 ip 10.10.4.20
switch-B(config-if-vl50)# exitVRRP Example 3: Two Virtual Routers on Two LANs
The network diagram displays Example 3. Three switches are configured as VRRP routers to form four virtual router groups two groups on each of two LANs.
- Router A is the master for virtual router 10 and backup for virtual router 20 on vlan 100.
- Router A is the master for virtual router 30 and backup for virtual router 40 on vlan 150.
- Router B is the master for virtual router 20 and backup for virtual router 10 on vlan 100.
- Router C is the master for virtual router 40 and backup for virtual router 30 on vlan 150.
- VRRP advertisement interval is set to one second on all virtual routers.
- Priority preemption is disabled on all virtual routers.
Switch Code that Implements Router A on the First Switch
switch-A(config)# interface vlan 100
switch-A(config-if-vl100)# ip address 10.10.4.1/24
switch-A(config-if-vl100)# no vrrp 10
switch-A(config-if-vl100)# vrrp 10 priority 200
switch-A(config-if-vl100)# no vrrp 10 preempt
switch-A(config-if-vl100)# vrrp 10 ip 10.10.4.10
switch-A(config-if-vl100)# vrrp 10 advertisement interval 1
switch-A(config-if-vl100)# no vrrp 20
switch-A(config-if-vl100)# no vrrp 20 preempt
switch-A(config-if-vl100)# vrrp 20 ip 10.10.4.20
switch-A(config-if-vl100)# interface vlan 150
switch-A(config-if-vl150)# ip address 40.10.5.7/24
switch-A(config-if-vl150)# no vrrp 30
switch-A(config-if-vl150)# vrrp 30 priority 200
switch-A(config-if-vl150)# no vrrp 30 preempt
switch-A(config-if-vl150)# vrrp 30 ip 40.10.5.31
switch-A(config-if-vl100)# vrrp 30 advertisement interval 1
switch-A(config-if-vl150)# no vrrp 40
switch-A(config-if-vl150)# no vrrp 40 preempt
switch-A(config-if-vl150)# vrrp 40 ip 40.10.5.32
switch-A(config-if-vl150)# exitSwitch Code that Implements Router B on the Second Switch
switch-B(config)# interface vlan 100
switch-B(config-if-vl100)# ip address 10.10.4.2/24
switch-B(config-if-vl100)# no vrrp 10
switch-B(config-if-vl100)# no vrrp 10 preempt
switch-B(config-if-vl100)# vrrp 10 ip 10.10.4.10
switch-B(config-if-vl100)# no vrrp 20
switch-B(config-if-vl100)# vrrp 20 priority 200
switch-B(config-if-vl100)# no vrrp 20 preempt
switch-B(config-if-vl100)# vrrp 20 ip 10.10.4.20
switch-A(config-if-vl100)# vrrp 20 advertisement interval 1
switch-B(config-if-vl100)# exitSwitch Code that Implements Router C on the Third Switch
switch-C(config)# interface vlan 150
switch-C(config-if-vl150)# ip address 40.10.5.8/24
switch-C(config-if-vl150)# no vrrp 30
switch-C(config-if-vl150)# no vrrp 30 preempt
switch-C(config-if-vl150)# vrrp 30 ip 40.10.5.31
switch-C(config-if-vl150)# no vrrp 40
switch-C(config-if-vl150)# vrrp 40 priority 200
switch-C(config-if-vl150)# no vrrp 40 preempt
switch-C(config-if-vl150)# vrrp 40 ip 40.10.5.32
switch-A(config-if-vl100)# vrrp 40 advertisement interval 1
switch-C(config-if-vl150)# exitVARP Example
This section provides code that implements a VARP configuration. The network diagram displays the Example 1 network. Two switches in an MLAG domain are configured as VARP routers.
The following code configures 10.10.4.10 as the virtual IP address for VLAN 50, 10.24.4.1 as the virtual IP address for VLAN 70, and 001c.7300.0999 as the virtual MAC address on both switches.
Switch Code that Implements VARP on the First Switch
switch-A(config)# ip virtual-router mac-address 001c.7300.0999
switch-A(config)# interface vlan 50
switch-A(config-if-vl50)# ip address 10.10.4.1/24
switch-A(config-if-vl50)# ip virtual-router address 10.10.4.10
switch-A(config-if-vl50)# interface vlan 70
switch-A(config-if-vl70)# ip address 10.24.4.17/24
switch-A(config-if-vl70)# ip virtual-router address 10.24.4.1
switch-A(config-if-vl70)# exitSwitch Code that Implements VARP on the Second Switch
switch-B(config)# ip virtual-router mac-address 001c.7300.0999
switch-B(config)# interface vlan 50
switch-B(config-if-vl50)# ip address 10.10.4.2/24
switch-B(config-if-vl50)# ip virtual-router address 10.10.4.10
switch-B(config-if-vl50)# interface vlan 70
switch-B(config-if-vl70)# ip address 10.24.4.18/24
switch-B(config-if-vl70)# ip virtual-router address 10.24.4.1
switch-B(config-if-vl70)# exitVRRP and VARP configuration Commands
This section contains descriptions of CLI commands that support VRRP and VARP.
Global configuration Commands
Interface configuration CommandsEthernet, port channel, and VLAN Interfaces
- ip virtual-router address
- ipv6 virtual-router address
- no vrrp
- vrrp advertisement interval
- vrrp disabled
- vrrp ipv4
- vrrp ipv4 checksum pseudo-header exclude
- vrrp ipv4 secondary
- vrrp ipv4 version
- vrrp ipv6
- vrrp mac-address advertisement-interval
- vrrp peer authentication
- vrrp preempt
- vrrp preempt delay
- vrrp priority-level
- vrrp session description
- vrrp timers delay reload
- vrrp tracked-object
Privileged EXEC Commands
ip fhrp accept-mode
The ip fhrp accept-mode command configures the switch to permit SSH access to the VRRP Master and VARP Master router. All routers within a VRRP or VARP group should be configured consistently. By default, SSH access to the VRRP and VARP Master routers is not permitted.
The no ip fhrp accept-mode and default ip fhrp accept-mode commands restores the default SSH access availability by removing the ip fhrp accept-mode command from running-config.
Command Mode
Global configuration
Command Syntax
ip fhrp accept-mode
no ip fhrp accept-mode
default ip fhrp accept-mode
Example
switch(config)# ip fhrp accept-mode
switch(config)# show running-config
!
ip fhrp accept-mode
!
switch(config)#ip virtual-router address
The ip virtual-router address command assigns a virtual IPv4 address to the VLAN interface being configured. (To assign a virtual IPv6 address to a VLAN interface, use the ipv6 virtual-router address command.) Unlike VRRP, the virtual IP address does not have to be in the same subnet as the physical interface.
A virtual IP address may optionally be configured with a subnet, but doing so will modify the behavior of ARP requests sent from the router. When the router sends an ARP request for an IP address in a virtual subnet, the ARP request will use the virtual IP address as the source IP address and the virtual MAC address as the source MAC address inside the ARP header. For virtual IP addresses configured without the subnet option, no modifications are made to outgoing ARP requests.
A maximum of 500 virtual IP addresses can be assigned to a VLAN interface. All virtual addresses on all VLAN interfaces resolve to the same virtual MAC address configured through the ip virtual-router mac-address command.
This command is typically used in MLAG configurations to create identical virtual routers on switches connected to the MLAG domain through an MLAG.
The no ip virtual-router address and default ip virtual-router address commands remove the specified virtual IP address from the configuration mode interface by deleting the corresponding ip virtual-router address command from running-config. If the command does not specify an address, all virtual IPv4 addresses are removed from the interface.
Command Mode
Interface-VLAN configuration
Command Syntax
ip virtual-router address ipv4_addr
no ip virtual-router address [ipv4_addr]
default ip virtual-router address [ipv4_addr]
Parameter
ipv4_addr IP address of router. Dotted decimal notation.
- These commands configure a Switch Virtual Interface (SVI) and a virtual IP
address for vlan
10.
switch(config)# interface vlan 10 switch(config-if-Vl10)# ip address 10.0.0.2/24 switch(config-if-Vl10)# ip virtual-router address 10.0.0.6 switch(config-if-Vl10)# exit - These commands configure a Switch Virtual Interface (SVI) and a virtual IP
address with a subnet for vlan 10. A static route
is added to indicate that the virtual subnet is reachable through
vlan
10.
switch(config)# ip route 192.0.0.0/24 vlan 10 switch(config)# interface vlan 10 switch(config-if-Vl10)# ip address 10.0.0.2/24 switch(config-if-Vl10)# ip virtual-router address 192.0.0.6/24 switch(config-if-Vl10)# exit
ip virtual-router mac-address
The ip virtual-router mac-address command assigns a virtual MAC address to the switch. The switch maps all virtual router IP addresses to this MAC address. The address is receive-only; the switch never sends packets with this address as the source. The virtual router is not configured on the switch until this virtual mac-address is assigned.
This command is typically used in MLAG configurations to create identical virtual routers on switches connected to the MLAG domain through an MLAG. When the destination MAC of a packet destined to a remote network matches the virtual MAC address, the MLAG peer forwards the traffic to the next hop destination. Each MLAG peer must have the same routes available, either through static configuration or learned through a dynamic routing protocol.
The no ip virtual-router mac-address command removes a virtual MAC address from the interface by deleting the corresponding ip virtual-router mac-address command from running-config.
Command Mode
Global configuration
Command Syntax
ip virtual-router mac-address mac_addr
no ip virtual-router mac address [mac_addr]
Parameter
mac_addr MAC IP address (dotted hex notation). Select an address does not appear on the switch.
Example
switch(config)# ip virtual-router mac-address 001c.7300.0099
switch(config)#ip virtual-router mac-address advertisement-interval
The ip virtual-router mac-address advertisement interval command specifies the period between the transmission of consecutive gratuitous ARP requests that contain the virtual router mac address for each virtual-router IP address configured on the switch. The default period is 30 seconds.
The no ip virtual-router mac-address advertisement-interval command restores the default period of 30 seconds by removing the ip virtual-router mac-address advertisement-interval command from running-config.
Command Mode
Global configuration
Command Syntax
ip virtual-router mac-address advertisement-interval period
no ip virtual-router mac-address advertisement-interval
default ip virtual-router mac-address advertisement-interval
Parameter
period advertisement interval (seconds). Values range from 0 to 86400. Default is 30.
Example
switch(config)# ip virtual-router mac-address advertisement-interval 60
switch(config)#ipv6 virtual-router address
The ipv6 virtual-router address command assigns a virtual IPv6 address to the VLAN interface being configured. (To assign a virtual IPv4 address to a VLAN interface, use the ip virtual-router address command.) Unlike VRRP, the virtual IP address does not have to be in the same subnet as the physical interface.
A maximum of 500 virtual IP addresses can be assigned to a VLAN interface. All virtual addresses on all VLAN interfaces resolve to the same virtual MAC address configured through the ip virtual-router mac-address command.
This command is typically used in MLAG configurations to create identical virtual routers on switches connected to the MLAG domain through an MLAG.
The no ipv6 virtual-router address and default ipv6 virtual-router address commands remove the specified virtual IPv6 address from the configuration mode interface by deleting the corresponding ipv6 virtual-router address command from running-config. If the command does not specify an address, all virtual IPv6 addresses are removed from the interface.
Command Mode
Interface-VLAN configuration
Command Syntax
ipv6 virtual-router address net_addr
no ipv6 virtual-router address [net_addr]
default ipv6 virtual-router address [net_addr]
Parameter
net_addr network IPv6 address.
Example
switch(config)# interface vlan 10
switch(config-if-Vl10)# ipv6 address 2001:0DB8:0:1::1/64
switch(config-if-Vl10)# ipv6 virtual-router address 2001:0DB8:0:1::2
switch(config-if-Vl10)# exitno vrrp
The no vrrp command removes all VRRP configuration commands for the specified virtual router on the configuration mode interface. The default vrrp command also reverts VRRP configuration parameters to default settings by removing the corresponding vrrp commands.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
no vrrp group
default vrrp group
Parameter
group Virtual Router Identifier (VRID). Values range from 1 to 255.
Example
switch(config)# interface vlan 15
switch(config-if-vl15)# no vrrp 10
switch(config-if-vl15)#show ip virtual-router
The show ip virtual-router command displays the virtual MAC address assigned to the switch and all virtual IP addresses assigned to each VLAN interface.
Command Mode
EXEC
Command Syntax
show ip virtual-router
- IP virtual router is not configured a virtual MAC address is not assigned to the switch.
- No interface with virtual IP address no virtual IP addresses are assigned to any VLAN interfaces.
- This command displays a table of information for VRRP groups on the
switch.
switch# show ip virtual-router IP virtual router is configured with MAC address: 24cd.5a29.cc31 Interface IP Address Virtual IP Address Status Protocol Vlan15 10.1.1.3/24 10.1.1.15 up up Vlan15 10.1.1.3/24 10.1.1.16 up up Vlan15 10.1.1.3/24 10.1.1.17 up up Vlan20 10.12.1.6/24 10.1.1.51 up up Vlan20 10.12.1.6/24 10.1.1.53 up up Vlan20 10.12.1.6/24 10.1.1.55 up up switch# - This command generates a response that indicates a virtual MAC address is
not assigned to the
switch.
switch# show ip virtual-router IP virtual router is not configured switch#
show ipv6 virtual-router
The show ipv6 virtual-router command displays the virtual MAC address assigned to the switch and all virtual IPv6 addresses assigned to each VLAN interface.
Command Mode
EXEC
Command Syntax
show ipv6 virtual-router
- IPv6 virtual router is not configured a virtual MAC address is not assigned to the switch.
- No interface with virtual IPv6 address no virtual IPv6 addresses are assigned to any VLAN interfaces.
Example
switch# show ipv6 virtual-router
IP virtual router is configured with MAC address: 001c.7300.0099
MAC address advertisement interval: 30 seconds
Interface Vlan4094
State is up
Protocol is up
IPv6 address
2001:b8:2001::1011/64
Virtual IPv6 address
2001:db8:ac10:fe01::
switch#show vrrp
The show vrrp command displays information about the Virtual Router Redundancy Protocol (VRRP) groups configured on a specified interface. Parameter options control the amount and formatting of the displayed information.
Command Mode
Privileged EXEC
Command Syntax
show vrrp [INFO_LEVEL] [STATES]
show vrrp INTF GROUP_NUM [INFO_LEVEL] [STATES]
show vrrp GROUP_NUM INTF_GROUP [INFO_LEVEL] [STATES]
- INTF specifies the VRRP groups for which the command
displays status. When the parameter is omitted or specifies only an
interface, the group list is filtered by the STATES parameter.
- no parameter specified groups on all interfaces.
- interface ethernet e_num specified groups on Ethernet interface.
- interface loopback l_num specified groups on loopback interface.
- interface management m_num specified groups on management interface.
- interface port-channel p_num specified groups on port channel interface.
- interface vlan v_num specified groups on VLAN interface.
- interface VXLAN vx_num specified groups on VXLAN interface.
- GROUP_NUM the VRRP ID number of the group for which
the command displays status.
- no parameter all groups on specified interface.
- vrid_num Virtual Router Identifier (VRID). Value ranges from 1 to 255.
- INFO_LEVEL Specifies format and amount of displayed
information. Options include:
- no parameter displays a block of data for each VRRP group.
- brief displays a single table that lists information for all VRRP groups.
- STATES Specifies the groups, by VRRP router state,
that are displayed. Options include:
- no parameter displays data for groups in the master or backup states.
- all displays all groups, including groups in the stopped and interface down states.
- This command displays a table of information for VRRP groups on the
switch.
switch# show vrrp brief Interface Id Ver Pri Time State VrIps Vlan1006 3 2 100 3609 Master 127.38.10.2 Vlan1006 4 3 100 3609 Master 127.38.10.10 Vlan1010 1 2 100 3609 Master 128.44.5.3 Vlan1014 2 2 100 3609 Master 127.16.14.2 switch> - This command displays data blocks for all VRRP groups on vlan
46, regardless of the VRRP
state.
switch# show vrrp interface vlan 1006 all Vlan1010 - Group 1 VRRP Version 2 State is Stopped Virtual IPv4 address is 128.44.5.3 Virtual MAC address is 0000.5e00.0101 Mac Address Advertisement interval is 30s VRRP Advertisement interval is 1s Preemption is enabled Preemption delay is 0s Preemption reload delay is 0s Priority is 100 Master Router is 0.0.0.0 Master Advertisement interval is 1s Skew time is 0.609s Master Down interval is 3.609s switch# - This command displays data for all VRRP group 2 on
vlan
1014.
switch# show vrrp interface vlan 1014 group 2 Vlan1006 - Group 2 VRRP Version 2 State is Master Virtual IPv4 address is 127.38.10.2 Virtual MAC address is 0000.5e00.0103 Mac Address Advertisement interval is 30s VRRP Advertisement interval is 1s Preemption is enabled Preemption delay is 0s Preemption reload delay is 0s Priority is 100 Master Router is 127.38.10.1 (local), priority is 100 Master Advertisement interval is 1s Skew time is 0.609s Master Down interval is 3.609s switch#
vrrp advertisement interval
The vrrp advertisement interval command configures the interval between successive advertisement messages that the switch sends to VRRP routers in the specified virtual router group. The switch must be the groups Master virtual router to send advertisement messages. The advertisement interval must be configured identically on all physical routers in the virtual router group.
The advertisement interval also influences the timeout interval that defines when the virtual router becomes the master virtual router. When preemption is enabled, the virtual router becomes the master when three times the advertisement interval elapses after the switch detects master router priority conditions.
The no vrrp advertisement interval and default vrrp advertisement interval commands restore the default advertisement interval of one second for the specified virtual router by removing the corresponding vrrp advertisement interval command from running-config. The no vrrp command also removes the vrrp advertisement interval command for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group advertisement interval adv_time
no vrrp group advertisement interval
default vrrp group advertisement interval
- group Virtual Router Identifier (VRID). Values range from 1 to 255.
- adv_time advertisement interval (seconds). Values range from 1 to 255. Default value is 1.
Example
switch(config)# interface vlan 100
switch(config-if-vl100)# vrrp 35 advertisement interval 5
switch(config-if-vl100)#vrrp disabled
The vrrp disabled command places the switch in stopped state for the specified virtual router. While in stopped state, the switch cannot act as a master or backup router for the virtual router group.
The no vrrp disabled and default vrrp disabled commands remove the corresponding vrrp disabled command from running-config. This changes the switchs virtual router state to backup or master if the virtual router is properly configured.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group disabled
no vrrp group disabled
default vrrp group disabled
Parameter
group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- These commands place the switch in stopped mode for virtual router
24 on vlan
20.
switch(config)# interface vlan 20 switch(config-if-vl20)# vrrp 24 disabled switch(config-if-vl20)# - This command moves the switch out of stopped mode for virtual router
24 on vlan
20.
switch(config-if-vl20)# no vrrp 24 disabled switch(config-if-vl20)#
vrrp ipv4
The vrrp ipv4 command configures the primary IP address for the specified VRRP virtual router. The command also activates the virtual router if the primary address is contained in the interfaces subnet. A VRRP virtual routers configuration may contain only one primary IP address assignment command; subsequent vrrp ipv4 commands replace the existing primary address assignment.
The vrrp ipv4 secondary command assigns a secondary IP address to the VRRP virtual router.
The no vrrp ipv4and default vrrp ipv4 commands disable the VRRP virtual router and deletes the primary IP address by removing the corresponding vrrp ipv4 statement from running-config. The no vrrp command also removes the vrrp ipv4 command for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group ipv4 ipv4_address
no vrrp group ipv4 ipv4_address
default vrrp group ipv4 ipv4_address
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- ipv4_address IPv4 address of the virtual router.
Related Command
Example
switch(config)# interface vlan 20
switch(config-if-vl20)# vrrp 15 ipv4 10.1.1.5
switch(config-if-vl20)#vrrp ipv4 checksum pseudo-header exclude
This command excludes the pseudo-header in IPv4 VRRPv3 checksum calculation on the VRRP group on the configuration mode interface of the switch and supports IPv4 VRRPv3 interoperability.
The no form of the command deletes the vrrp ipv4 checksum pseudo-header exclude configuration from the Ethernet interface on the switch.
The exit command returns the switch to global configuration mode.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group ipv4 checksum pseudo-header exclude
no vrrp group ipv4 checksum pseudo-header exclude
Parameter
group Virtual Router IDentifier (VRID). Values range from 1 to 255.
Example
switch(config-if-Et1)# vrrp 1 ipv4 checksum pseudo-header exclude vrrp ipv4 secondary
The vrrp ipv4 secondary command assigns a secondary IP address to the specified virtual router. Secondary IP addresses are an optional virtual router parameter. A virtual router may contain multiple secondary address commands. The IP address list must be identical for all VRRP routers in a virtual router group.
The virtual router is assigned a primary IP address with the vrrp ipv4 command.
The no vrrp ipv4 secondary and default vrrp ipv4 secondary commands remove the secondary IP address for the specified VRRP virtual router by deleting the corresponding vrrp ipv4 secondary statement from running-config. The no vrrp command also removes all vrrp ipv4 secondary commands for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group ipv4ipv4_addr secondary
no vrrp group ipv4ipv4_addr secondary
default vrrp group ipv4ipv4_addr secondary
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- ipv4_addr secondary IPv4 address of the virtual router.
Related Command
Example
switch(config)# interface vlan 20
switch(config-if-vl20)# vrrp 15 ipv4 10.2.4.5 secondary
switch(config-if-vl20)#vrrp ipv4 version
The vrrp ipv4 version command enables VRRP on the configuration mode interface and configures the VRRP version for the specified VRRP virtual router.
The no vrrp ipv4 version and default vrrp ipv4 version commands restore the default VRRP version to VRRPv2 by removing the corresponding vrrp ipv4 version statement from running-config.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group ipv4 version VERSION_NUMBER
no vrrp group ipv4 version
default vrrp group ipv4 version
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- VERSION_NUMBER Specifies VRRP version that the
switch uses. Default value is 2 (VRRPv2) Options include:
- 2 VRRP v2 supports IPv4 environment.
- 3 VRRP v3 supports IPv4 and IPv6 environment.
- This command enables VRRPv3 for IPv6 on interface ethernet
3.
switch#(config)# interface ethernet 3 switch#(config-if-Et3)# vrrp 1 ipv4 version 3 - This command removes VRRPv3 from interface ethernet
3 and reverts to the default
VRRPv2.
switch#(config)# interface ethernet 3 switch#(config-if-Et3)# no vrrp 1 ipv4 version
vrrp ipv6
The vrrp ipv6 command configures the IPv6 address for the specified VRRP virtual router. The command also activates the virtual router if the primary address is contained in the interfaces subnet.
The no vrrp ipv6 and default vrrp ipv6 commands disable the VRRP virtual router and deletes the IPv6 address by removing the corresponding vrrp ipv6 statement from running-config. The no vrrp command also removes the vrrp ipv6 command for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group ip ipv6_address
no vrrp group ip ipv6_address
default vrrp group ip ipv6_address
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- ipv6_address IPv6 address of the virtual router.
- This command enables address 2001:db8:0:1::1 for
IPv6 VRRP on vlan
20.
switch(config)# interface vlan 20 switch(config-if-vl20)# vrrp 3 ipv6 2001:db8:0:1::1 switch(config-if-vl20)# - This command disables VRRPv3 on vlan 20 from
virtual router
3.
switch(config)# interface vlan 20 switch(config-if-vl20)# no vrrp 3 ipv6 2001:db8:0:1::1 switch(config-if-vl20)#
vrrp mac-address advertisement-interval
The vrrp mac-address advertisement-interval command specifies the interval between advertisement packets sent by the master router to the VRRP group members.
The vrrp mac-address advertisement-interval 0, no vrrp mac-address advertisement-interval and default vrrp mac-address advertisement-interval commands disable the feature by removing the vrrp mac-address advertisement-interval command from running-config.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group mac-address advertisement-interval period
no vrrp group mac-address
default vrrp group mac-address
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- period interval in which the master router sends advertisement packets (seconds). Value ranges from 0 to 3600. Selecting 0 as the interval disables this feature.
- This command specifies the interval between advertisement packets sent to
the members of VRRP group 3 on vlan
20.
switch(config)# interface vlan 20 switch(config-if-vl20)# vrrp 3 mac-address advertisement-interval 60 switch(config-if-vl20)# - This command disables the feature on vlan
20.
switch(config)# interface vlan 20 switch(config-if-vl20)# no vrrp 3 mac-address advertisement-interval switch(config-if-vl20)#
vrrp peer authentication
The vrrp peer authentication command configures parameters the switch uses to authenticate virtual router packets it receives from other VRRP routers in the group.
The no vrrp peer authentication and default vrrp peer authentication commands disable VRRP peer authentication of packets from the specified virtual router by removing the corresponding vrrp peer authentication command from running-config . The no vrrp command also removes the vrrp peer authentication command for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group peer authentication AUTH_PARAMETER
no vrrp group peer authentication
default vrrp group peer authentication
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- AUTH_PARAMETER encryption level and authentication
key used by router. Options include:
- text text_key plain-text authentication, text_key is text.
- text_key plain-text authentication, text_key is text.
- ietf-md5 key-string 0 text_key IP authentication of MD5 key hash, text_key is text.
- ietf-md5 key-string text_key IP authentication of MD5 key hash, text_key is text.
- ietf-md5 key-string 7 coded_key IP authentication of MD5 key hash, coded_key is MD5 hash.
Guidelines
This command is applicable to VRRPv2 which supports IPv4 addresses only.
- This command implements plain-text authentication, using
12345 as the key, for virtual router
40 on vlan
100.
switch(config)# interface vlan 100 switch(config-if-vl100)# vrrp 40 peer authentication text 12345 switch(config-if-vl100)# - This command implements ietf-md5 authentication, using
12345 as the key.
switch(config-if-vl100)# vrrp 40 peer authentication ietf-md5 key-string 0 12345 switch(config-if-vl100)# - This command implements ietf-md5 authentication, using
12345 as the key. The key is entered as
the MD5 hash equivalent of the text
string.
switch(config-if-vl100)# vrrp 40 peer authentication ietf-md5 key-string 7 EA3TUPxdddFCLYT8mb+kxw== switch(config-if-vl100)#
vrrp preempt
The vrrp preempt command controls a virtual routers preempt mode setting. When preempt mode is enabled, if the switch has a higher priority it will preempt the current master virtual router. When preempt mode is disabled, the switch can become the master virtual router only when a master virtual router is not present on the subnet, regardless of VRRP priority level settings. By default, preempt mode is enabled.
The no vrrp preemptcand default vrrp preemptccommands disable preempt mode for the specified virtual router; the default vrrp preempt command stores a corresponding no vrrp preempt statement in running-config. The vrrp preempt command enables preempt mode by removing the corresponding no vrrp preempt statement from running-config.
The no vrrp command also enables preempt mode by removing the no vrrp preempt command for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group preempt
no vrrp group preempt
default vrrp group preempt
Parameter
group Virtual Router IDentifier (VRID). Values range from 1 to 255.
Related Command
- This command disables preempt mode for virtual router
20 on vlan
40.
switch(config)# interface vlan 40 switch(config-if-vl40)# no vrrp 20 preempt switch(config-if-vl40)# - This command enables preempt mode for virtual router
20 on vlan
40.
switch(config-if-vl40)# vrrp 20 preempt switch(config-if-vl40)#
vrrp preempt delay
The vrrp preempt delay command specifies the interval between a VRRP preemption event and the point when the switch becomes the master VRRP router. A preemption event is any event that results in the switch having the highest virtual router priority setting while preemption is enabled. The vrrp preempt command enables preemption for a specified virtual router.
- minimum time delays master VRRP takeover when VRRP is fully implemented.
- reload time delays master VRRP takeover after VRRP is initialized following a switch reload (boot).
Running-config maintains separate delay statements for minimum and reload parameters. Commands may list both parameters. Commands that list one parameter do not affect the omitted parameter. Values range from 0 to 3600 seconds (one hour). The default delay is zero seconds for both parameters.
The no vrrp preempt delay and default vrrp preempt delay commands reset the specified delay to the default of zero seconds. Commands that do no list either parameter resets both periods to zero. The no vrrp command also removes all vrrp preempt delay commands for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group preempt delay [MINIMUM_INTERVAL] [RELOAD_INTERVAL]
no vrrp group preempt delay [DELAY_TYPE]
default vrrp group preempt delay [DELAY_TYPE]
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- MINIMUM_INTERVAL period between preempt event and
takeover of master VRRP router role.
- no parameter minimum delay is not altered by command.
- minimum min_time delay during normal operation (seconds). Values range from 0 to 3600.
- RELOAD_INTERVAL period after reboot-VRRP
initialization and takeover of master VRRP router role.
- no parameter reload delay is not altered by command.
- reload reload_time delay after reboot (seconds). Values range from 0 to 3600.
- DELAY_TYPE delay type that is reset to default
value.
- no parameter reload and minimum delays are reset to default.
- minimum minimum delay is reset to default.
- reload reload delay is reset to default.
(DELAY_TYPE parameter is only used in no vrrp preempt delay and default vrrp preempt delay commands).
Related Command
- This command sets the minimum preempt time of 90
seconds for virtual router 20 on vlan
40.
switch(config)# interface vlan 40 switch(config-if-vl40)# vrrp 20 preempt delay minimum 90 switch(config-if-vl40)# - This command sets the minimum and reload preempt time to
0 for virtual router
20 on vlan
40.
switch(config-if-vl40)# no vrrp 20 preempt delay switch(config-if-vl40)#
vrrp priority-level
The vrrp priority-level command configures the switchs priority setting for a VRRP virtual router. Priority values range from 1 to 254. The default value is 100.
The router with the highest VRRP priority level setting for a group becomes the master virtual router for that group. The master virtual router controls the IP address and is responsible for forwarding traffic sent. The vrrp preempt command controls the time when a switch can become the master virtual router.
The no vrrp priority-level and default vrrp priority-level commands restore the default priority of 100 to the virtual router on the configuration mode interface by removing the corresponding vrrp priority-level command from running-config. The no vrrp command also removes the vrrp priority-level command for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group priority-level level
no vrrp group priority-level level
default vrrp group priority-level level
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- level priority setting for the specified virtual router. Values range from 1 to 254.
Example
switch(config)# interface vlan 20
switch(config-if-vl20)# vrrp 45 priority-level 250
switch(config-if-vl20)#vrrp session description
The vrrp session description command associates a text string to a VRRP virtual router on the configuration mode interface. The string has no functional impact on the virtual router. The maximum length of the string is 80 characters.
The no vrrp session description and default vrrp session description commands remove the text string association from the VRRP virtual router by deleting the corresponding vrrp session description command from running-config. The no vrrp command also removes the vrrp session description command for the specified virtual router.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group session description label_text
no vrrp group session description
default vrrp group session description
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- label_text text that describes the virtual router. Maximum string length is 80 characters.
Example
switch(config)# interface vlan 20
switch(config-if-vl20)# vrrp 15 session description Laboratory Router
switch(config-if-vl20)#vrrp timers delay reload
The vrrp timers delay reload command delays the time for VRRP initialization after a system reboot.
The no vrrp timers delay reload and default vrrp timers delay reload commands restore the default value of 0 by deleting the vrrp timers delay reload statement from running-config.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group timers delay reload [INTERVAL]
no vrrp group timers delay reload
default vrrp group timers delay reload
Parameters
- no parameter Default value of 0 seconds.
- 0 to 3600 seconds. Ranges between 0 to 60 minutes.
- These commands configure the VRRP reload delay interval to
15
minutes.
switch(config)# interface vlan 100 switch(config-if-Vl100)# vrrp 2 timers delay reload 900 switch(config-if-Vl100)# - These commands removes the VRRP reload delay
interval.
switch(config)# interface vlan 100 switch(config-if-Vl100)# no vrrp 2 timers delay reload switch(config-if-Vl100)#
vrrp tracked-object
The vrrp tracked-object command configures the VRRP client process on the configuration mode interface to track the specified tracked object and react when its status changes to down. The tracked object is created by the track command.
The no vrrp tracked-object and default vrrp tracked-object commands cause the VRRP client process to stop tracking the specified tracked object by removing the corresponding vrrp tracked-object command from running-config.
Command Mode
Interface-Ethernet configuration
Interface-port-channel configuration
Interface-VLAN configuration
Command Syntax
vrrp group tracked-object object_name ACTION amount
no vrrp group tracked-object object_name ACTION
default vrrp group tracked-object object_name ACTION
- group Virtual Router IDentifier (VRID). Values range from 1 to 255.
- object_name name of tracked object.
- amount amount to decrement VRRP priority level. Values range from 1 to 254.
- ACTION The action that VRRP is to take when the tracked
objects status changes to down. Options include:
- decrement decrease VRRP priority level by amount.
- shutdown shut down VRRP on the configuration mode interface.
- If both decrement and shutdown are configured on the same interface for the same VRRP group, then VRRP will be shut down on the interface if the tracked object is down.
Related Commands
Example
switch(config-if-Et5)# vrrp 1 tracked-object eth8 shutdown
switch(config-if-Et5)#