Alcatel-Lucent 7950 Quality Of Service Manual page 253

sla — When the sap-egress policy is applied to an sla-profile for a subscriber, the parent schedulers of the
queues need to be configured in the scheduler-policy applied to the same sla-profile.
If this parameter is configured within a sap-egress policy that is applied to any object except of the
egress of an sla-profile, the configured parent schedulers will not be found and so the queues will not be
parented and will be orphaned.
policer
Syntax policer policer-id [ {[port-redirect-group-queue] [queue queue-id]} | {group queue-group-name
[instance instance-id] [queue group-queue-id]} ]
no policer
Context config>qos>sap-egress>fc
Description
Within a sap-egress QoS policy forwarding class context, the policer command is used to map packets that
match the forwarding class to the specified policer-id. The specified policer-id must already exist within the
sap-egress QoS policy. The forwarding class of the packet is first discovered at ingress based on the ingress
classification rules. When the packet arrives at egress, the sap-egress QoS policy may match a forwarding
class reclassification rule which overrides the ingress derived forwarding class. The forwarding class
context within the sap-egress QoS policy is then used to map the packet to an egress queue (using the queue
queue-id, or port-redirect-group queue queue-id, or group queue-group-name instance instance-id queue
queue-id commands) or an egress policer (policer policer-id). The queue and policer commands within the
forwarding class context are mutually exclusive. By default, the forwarding class is mapped to the SAP
egress default queue (queue 1). If the policer policer- id command is executed, any previous policer mapping
or queue mapping for the forwarding class is overridden if the policer mapping is successful.
A policer defined within the sap-egress policy is not actually created on an egress SAP or a subscriber using
an sla-profile where the policy is applied until at least one forwarding class is mapped to the policer. If
insufficient policer resources exist to create the policer for a SAP or subscriber or egress policing is not
supported on the port associated with the SAP or subscriber, the initial forwarding class mapping will fail.
Packets that are mapped to an egress policer that are not discarded by the policer must be placed into a
default queue on the packets destination port. The system uses egress port queue groups for this purpose. An
egress queue group named policer-output-queues is automatically created on each port that support egress
policers. By default, the system uses the forwarding class mappings within this queue group to decide which
queue within the group will receive each packet output from the policer. This default policer output queuing
behavior may be overridden for non-subscriber packets by redirection to a queue group. The name and
instance of the queue group to redirect to is either spcecifed in the QoS policy itself, or the fact that a
forwarding class must be redirected is simply identified in the QoS policy and the specific queue group
instance is only identified at the time the QoS poicy is applied:
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7950 XRS Quality of Service Guide
If the policer policer-id command is successfully executed, the default egress queuing is performed
for the forwarding class using the policer-output-queues queue group and the queue-id within the
group based on the forwarding class map from the group template
If the policer policer-id queue queue-id command is successfully executed, the specified SAP
queue-id within egress QoS policy is used instead of the default policer output queues.
If the policer policer-id port-redirect-group-queue keyword is successfully executed, the system
will map the forwarding class to the queue within the egress queue group instance specified at the
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