Avaya Inc. – External Distribution
Filter Set Resource Usage: as previously noted, a filter set is essentially a named collection of policies
that reference classifier and action criteria for identifying and processing traffic. Policies, filters and related
QoS components (e.g., meters, counters) consume hardware resources when applied to a port. A filter
set therefore requires hardware resources equivalent to the sum of the resources required to support the
individual policies, filters, etc. that comprise the filter set.
When installed, a single filter set classifier element or a classifier block consumes one precedence mask
(i.e., resource usage equivalent to a policy referencing a single filter or a filter block). Thus the number of
precedence levels/masks required for filter set installation equals the number of classifiers and unique
classifier blocks included in the filter set. To ensure deterministic behavior, the required number of
precedence levels must be available and consecutive for a filter set installation to be successful. Consider
the following filter set:
qos traffic-profile classifier name fivePrecs dst-ip 1.2.3.4/32 drop-action enable
eval-order 1
qos traffic-profile classifier name fivePrecs dst-ip 1.2.3.5/32 drop-action enable
eval-order 2
qos traffic-profile classifier name fivePrecs dst-ip 1.2.3.6/32 drop-action enable
eval-order 3
qos traffic-profile classifier name fivePrecs ds-field 23 drop-action enable block
dscpBlk eval-order 10
qos traffic-profile classifier name fivePrecs ds-field 24 drop-action enable block
dscpBlk eval-order 11
qos traffic-profile classifier name fivePrecs protocol 111 drop-action enable block
protoBlk eval-order 20
qos traffic-profile classifier name fivePrecs protocol 112 drop-action enable block
protoBlk eval-order 21
qos traffic-profile set port 1-2 name fivePrecs track-statistics aggregate
Filter set “fivePrecs” contains 3 classifiers and 2 unique classifier blocks requiring that 5 consecutive
precedence levels be available on ports to which the filter set is applied. There is no requirement
regarding which precedence levels are available. The highest suitable starting precedence will be
selected automatically when the filter set is installed. For example, under a default configuration scenario,
“fivePrecs” would consume precedence masks 9 – 13 if installed on port 1 and 2 of a 5698:
5650TD(config)#show qos diag
Unit/Port Mask Precedence Usage
16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
--------- ---------------------------------------------------------------
1/1 AR DR DH Q Q Q Q Q Q Q
1/2 AR DR DH Q Q Q Q Q Q Q
AR=ARP DH=DHCP Q=QoS
On an ERS 4500 switch, we could not apply the above traffic profile as by default, only precedence levels
3 – 6 are available. However, we could disable DHCP-Relay freeing up precedence level 7 or we could
ether assign an interface group of trusted or unrestricted to free up both precedence levels 1 and 2. For
example, assuming we disable DHPC-Relay, “fivePrecs” would consume precedence masks 3 - 7 if
installed on port 1 and 2 of a 4526:
no ip dhcp-relay
qos traffic-profile classifier name fivePrecs dst-ip 1.2.3.4/32 drop-action enable
eval-order 1
To Next Page
Loading...
