Alcatel-Lucent 7710 SR OS Configuration Manual page 307

Multiple unique (different prefix/mask-length) route-unknown event nodes can be configured within
the priority-event node up to the maximum limit of 32 events.
The route-unknown command can reference any valid IP addres mask-length pair. The IP address
and associated mask length define a unique IP router prefix. The dynamic monitoring of the route
prefix results in one of the following event operational states:
An existing route prefix in the RTM must be active (used by the IP forwarding engine) to clear the
event operational state. It may be less specific (the defined prefix may be contained in a larger prefix
according to Classless Inter-Domain Routing (CIDR) techniques) if the event has the less-specific
statement defined. The less specific route that incorporates the router prefix may be the default route
(0.0.0.0) if the less-specific allow-default statement is defined. The matching prefix may be required
to have a specific next hop IP address if defined by the event next-hop command. Finally, the source
of the RTM prefix may be required to be one of the dynamic routing protocols or be statically defined
if defined by the event protocol command. If an RTM prefix is not found that matches all the above
criteria (if defined in the event control commands), the event is considered to be set. If a matching
prefix is found in the RTM, the event is considered to be cleared.
When an event transitions from clear to set, the set is processed ediately and must be reflected in the
associated virtual router instances in-use priority value. As the event transitions from clear to set, a
hold set timer is loaded with the value configured by the events hold-set command. This timer
prevents the event from clearing until it expires, damping the effect of event flapping. If the event
clears and becomes set again before the hold set timer expires, the timer is reset to the hold-set value,
extending the time before another clear can take effect.
The no form of the command is used to remove the specific prefix/mask-length monitoring event. The
event can be removed at anytime. When the event is removed, the in-use priority of all associated
7710 SR OS Router Configuration Guide
route-unknown
Operational State
Set – non-existent
Set – inactive
Set – wrong next hop
Set – wrong protocol
Set – less specific
found
Set – default best
match
Cleared – less specific
found
Cleared – found
The route does not exist in the route table.
The route exists in the route table but is not being used.
The route exists in the route table but does not meet the next-hop
requirements.
The route exists in the route table but does not meet the protocol
requirements.
The route exists in the route table but does is not an exact match and
does not meet any less-specific requirements.
The route exists in the route table as the default route but the default
route is not allowed for route matching.
A less specific route exists in the route table and meets all criteria
including the less-specific requirements.
The route exists in the route table manager and meets all criteria.
Description
VRRP
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