40-1
Chapter 40: Router Redundancy Commands
Router redundancy protocols use a virtual IP address to support a primary router
and multiple backup routers. The backup routers can be configured to take over the
workload if the master router fails, or can also be configured to share the traffic load.
The primary goal of router redundancy is to allow a host device which has been
configured with a fixed gateway to maintain network connectivity in case the primary
gateway goes down.
Virtual Router Redundancy Protocol Commands
To configure VRRP, select an interface on each router in the group that will
participate in the protocol as the master router or a backup router. To select a
specific device as the master router, set the address of this interface as the virtual
router address for the group. Now set the same virtual address and a priority on the
backup routers, and configure an authentication string. You can also enable the
preempt feature which allows a router to take over as the master router when it
comes on line if it has a higher priority than the currently active master router.
Table 40-1 Router Redundancy Commands
Command Groups
Function
Page
Virtual Router Redundancy
Protocol
Configures interface settings for VRRP
40-1
Table 40-2 VRRP Commands
Command
Function
Mode
Page
vrrp ip
Enables VRRP and sets the IP address of the virtual router IC
40-2
vrrp authentication
Configures a key used to authenticate VRRP packets
received from other routers
IC
40-3
vrrp priority
Sets the priority of this router in the VRRP group
IC
40-3
vrrp timers advertise
Sets the interval between successive advertisements by
the master virtual router
IC
40-4
vrrp preempt
Configures the router to take over as master virtual router
for a VRRP group if it has a higher priority than the current
master virtual router
IC
40-5
show vrrp
Displays VRRP status information
PE
40-6
show vrrp interface
Displays VRRP status information for the specified interface PE
40-8
show vrrp router counters
Displays VRRP statistics
PE
40-9
show vrrp interface counters Displays VRRP statistics for the specified interface
PE
40-9
clear vrrp router counters
Clears VRRP router statistics
PE
40-10
clear vrrp interface counters Clears VRRP interface statistics
PE
40-10
Summary of Contents for 8926EM
Page 6: ...ii ...
Page 34: ...Getting Started ...
Page 44: ...Introduction 1 10 1 ...
Page 62: ...Initial Configuration 2 18 2 ...
Page 64: ...Switch Management ...
Page 76: ...Configuring the Switch 3 12 3 ...
Page 118: ...Basic Management Tasks 4 42 4 ...
Page 164: ...User Authentication 6 28 6 ...
Page 176: ...Access Control Lists 7 12 7 ...
Page 284: ...Quality of Service 14 8 14 ...
Page 294: ...Multicast Filtering 15 10 15 ...
Page 300: ...Domain Name Service 16 6 16 ...
Page 310: ...Dynamic Host Configuration Protocol 17 10 17 ...
Page 320: ...Configuring Router Redundancy 18 10 18 ...
Page 344: ...IP Routing 19 24 19 ...
Page 356: ...Unicast Routing 20 12 20 Web Click Routing Protocol RIP Statistics Figure 20 5 RIP Statistics ...
Page 386: ...Unicast Routing 20 42 20 ...
Page 388: ...Command Line Interface ...
Page 400: ...Overview of the Command Line Interface 21 12 21 ...
Page 466: ...SNMP Commands 24 16 24 ...
Page 520: ...Access Control List Commands 26 18 26 ...
Page 546: ...Rate Limit Commands 30 2 30 ...
Page 612: ...VLAN Commands 34 24 34 ...
Page 626: ...Class of Service Commands 35 14 35 ...
Page 670: ...DHCP Commands 39 16 39 ...
Page 716: ...IP Interface Commands 41 36 41 ...
Page 768: ...IP Routing Commands 42 52 42 ...
Page 770: ...Appendices ...
Page 791: ......