Host Unreachable Priority Event; Route Unknown Priority Event - Alcatel-Lucent 7705 Configuration Manual

VRRP Priority Control Policies

Host Unreachable Priority Event

The host unreachable priority event creates a continuous ping task that is used to test
connectivity to a remote host. For the ping to be successful, the path to the remote host, and
the remote host itself, must be capable and configured to accept ICMP echo request and
replies.
The ping task is controlled by interval and size parameters that define how often the ICMP
request messages are transmitted and the size of each message. A historical missing reply
parameter defines if the ping destination is considered unreachable.
If the host is unreachable, the host unreachable priority event is considered true or set. If the
host is reachable, the host unreachable priority event is considered false or cleared.

Route Unknown Priority Event

The route unknown priority event defines a task that monitors the existence of a given route
prefix in the routing table of the system.
The route monitoring task can be constrained by a condition that allows a prefix that is less
specific than the defined prefix to be considered as a match. The source protocol can be
defined to indicate the protocol the installed route must be populated from. To further define
match criteria when multiple instances of the route prefix exist, an optional next-hop
parameter can be defined.
If a route prefix exists within the active route table that matches the defined match criteria,
the route unknown priority event is considered false or cleared. If a route prefix does not exist
within the active route table that matches the defined criteria, the route unknown priority
event is considered true or set.
224 7705 SAR OS Router Configuration Guide