IP Configuration: VRRP
Configuring VRRP
Cisco 350XG & 550XG Series 10G Stackable Managed Switches
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If a virtual router is the owner of the IP address, its VRRP priority is automatically
assigned with priority of 255 by the system, and the VRRP router (on which this
virtual router is assigned) automatically functions as a virtual router master if it is
up.
, if Router A, the virtual router master, fails, a selection process takes
place to determine if virtual router backups B or C must take over. If Routers B and
C are configured with the priorities of 101 and 100, respectively, Router B is
elected to become virtual router master because it has the higher priority. If both
have the same priority, the one with the higher IP address value is selected to
become the virtual router master.
By default, a preemptive feature is enabled, which functions as follows:
•
Enabled - When a VRRP router is configured with higher priority than the
current master is up, it replaces the current master.
•
Disabled - Even if a VRRP router with a higher priority than the current
master is up, it does not replace the current master. Only the original master
(when it becomes available) replaces the backup.
VRRP Advertisements
The virtual router master sends VRRP advertisements to routers which are in the
same group (configured with the same virtual router identification).
The VRRP advertisements are encapsulated in IP packets and sent to the IP v4
Multicast address assigned to the VRRP group. The advertisements are sent every
second by default; the advertisement interval is configurable.
The advertisement Interval is in mS (Range: 50 - 40950, Default: 1000). A non-
value is invalid.
•
In VRRP version 3, the operational advertise interval is rounded down the
nearest 10ms.
•
In VRRP version 2, the operational advertise interval is rounded down to the
nearest second. The minimum operational value is 1 sec.
Configuring VRRP
This feature can be configured in the following pages.
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