WebOS 10.0 Application Guide
Chapter 11: High Availability 261
212777-A, February 2002
When sharing is enabled, the master election process still occurs. Although the process does
not affect which switch processes packets that must be routed or that are destined for the vir-
tual server IP address, it does determine which switch sends advertisements and responds to
ARP requests sent to the virtual router’s IP address.
WebOS strongly recommends that sharing, rather than active-standby configurations, be used
whenever possible. Sharing offers both better performance and fewer service interruptions in
the face of fault conditions than active-standby configurations.
Tracking VRRP Router Priority
WebOS supports a tracking function that dynamically mo difies 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 rout ers in a LAN converge on the same switch. Tracking
ensures that the selected switch is the one that offers optimal network performance. For track-
ing to have any effect on virtual router operation, preemption must be enabled.
NOTE – Tracking only affects hot standby and active-standby configurations. It does not have
any effect on active-active sharing configurations.
WebOS can track the attributes listed in Ta ble 11 -3:
Table 11-3 VRRP Tracking Parameters
Parameter Description
Number of virtual routers in master mode
on the switch
/cfg/vrrp/track/vrs
Useful for ensuring that traffic for any particular cli-
ent/server pair is handled by the same switch, increasing
routing and load-balancing efficiency. This parameter
influences the VRRP router’s priority in both virtual inter-
face routers and virtual server routers.
Number of IP interfaces active on the
switch
/cfg/vrrp/track/ifs
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
both virtual interface routers and virtual server routers.
Number of active ports on the same VLAN
/cfg/vrrp/track/ports Helps elect the virtual routers with the most available
ports as the master. This parameter influences the VRRP
router’s priority in both virtual i nterface routers and virt ual
server routers.