IBM RackSwitch G8000 User Manual

302 RackSwitch G8000: Application Guide
IBM N/OS Extensions to VRRP
This section describes VRRP enhancements that are implemented in N/OS.
N/OS supports a tracking function that dynamically modifies the priority of a VRRP
router, based on its current state. The objective of tracking is to have, whenever
possible, the master bidding processes for various virtual routers in a LAN converge
on the same switch. Tracking ensures that the selected switch is the one that offers
optimal network performance. For tracking to have any effect on virtual router
operation, preemption must be enabled.
N/OS can track the attributes listed in Table 23 (Router VRRP mode):
Each tracked parameter has a user-configurable weight associated with it. As the
count associated with each tracked item increases (or decreases), so does the
VRRP router's priority, subject to the weighting associated with each tracked item. If
the priority level of a standby is greater than that of the current master, then the
standby can assume the role of the master.
See “Configuring the Switch for Tracking” on page 303 for an example on how to
configure the switch for tracking VRRP priority.
Table 23. VRRP Tracking Parameters
Parameter Description
Number of IP interfaces on the switch
that are active (“up”)
tracking-priority-increment
interfaces
Helps elect the virtual routers with the most
available routes as the master. (An IP
interface is considered active when there is
at least one active port on the same
VLAN.) This parameter influences the
VRRP router's priority in virtual interface
routers.
Number of active ports on the same
VLAN
tracking-priority-increment
ports
Helps elect the virtual routers with the most
available ports as the master. This
parameter influences the VRRP router's
priority in virtual interface routers.
Number of virtual routers in master
mode on the switch
tracking-priority-increment
virtual-routers
Useful for ensuring that traffic for any
particular client/server pair is handled by
the same switch, increasing routing
efficiency. This parameter influences the
VRRP router's priority in virtual interface
routers.

IBM RackSwitch G8000 Specifications

General

Brand	IBM
Model	RackSwitch G8000
Category	Network Router
Language	English