Configuring Authentication on VSRP Interfaces

If the interfaces on which you configure the VRID use authentication, the VSRP packets on those interfaces must also use the same authentication.
As a prerequisite, a VSRP session must be configured and running.
If you configure your device interfaces to use a simple password to authenticate traffic, VSRP interfaces can be configured with the same simple password, and VSRP packets that do not contain the password are dropped. If your interfaces do not use authentication, neither does VSRP. Repeat this task on all interfaces on all devices that support the VRID.
  1. From privileged EXEC mode, enter global configuration mode. 
    device# configure terminal
  2. Configure the VLAN on which a VSRP VRID is assigned. 
    device(config)# vlan 100
  3. Enter the simple text password configuration. 
    device(config-vlan-100)# vsrp auth-type simple-text-auth ourpword
  4. Verify the authentication type in effect on the ports in the VSRP VLAN
    device(config-vlan-100)# show vsrp
VLAN 100
 auth-type simple text password
 VRID 1
 ========
  State      Administrative-status Advertise-backup Preempt-mode save-current
  initialize enabled               enabled          true         false

  Parameter        Configured Current    Unit/Formula
  priority         100        0          (100-0)*(0.0/1.0)
  hello-interval   1          1          sec/1
  dead-interval    3          3          sec/1
  hold-interval    3          3          sec/1
  initial-ttl      2          2          hops

  Member ports:      ethe 1/1/1
  Operational ports: None
  Forwarding ports:  None
  Restart ports:     None
Parent topic: Virtual Switch Redundancy Protocol (VSRP)