Switch User Manual

Filters and QoS Configuration for ERS 5500
Technical Configuration Guide v2.0 NN48500-559
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External Distribution
12
Max = 11
4 7 Min = 100
Max = 111
8 15 Min = 1000
Max = 1111
80 95 Min = 10100000
Max = 10111111
3.4 Policies
• Packets received on an interface are matched against all policies associated with that
interface. Hence, all policies are applied to the packet.
• Policy precedence – the precedence attribute is used to specify the evaluation order of
policies that apply to the same interfaces. Policies with higher precedence (i.e., a larger
value) are applied before those with lower precedence (i.e., a smaller value). Precedence
values must be unique for all policies being applied to the same interface role.
• If one policy associated with the specific interface only specifies a value updating the
DSCP value while another policy associated with that same interface only specifies a
value for updating the 802.1p user priority value, both of these actions occur.
• If two policies on the specified interface request that the DSCP be updated but specify
different values - the value from the policy with the higher precedence will be used.
• Referenced component conflicts - action or meter criteria can be specified through
individual classifier blocks. When a policy references a classifier block and members of
the referenced block identify their own action or meter criteria, action and meter data
must not be specified by the policy.
• The actions applied to packets include those actions defined from user-defined policies
and those actions defined from system default policies. The user-defined actions always
carry a higher precedence than the system default actions. This means that, if user-
defined policies do not specify actions that overlap with the actions associated with
system default policies (for example, the DSCP and 802.1p update actions installed on
untrusted interfaces), the lowest precedence, default policy actions will be included in the
set of actions to be applied to the identified traffic.
• The following table displays the ERS 5500 default policy action with corresponding drop
actions. The drop action specifies whether a packet should be dropped, not dropped, or
deferred. A drop action of deferred-Pass specifies that a traffic flow decision will be
deferred to other installed policies.
Table 3: Default Policy Drop Action
ID Name Drop Update DSCP User Priority Drop
Precedence
1 Drop_Traffic drop Ignore Ignore highDropPrec
2 Standard_Service Don’t Drop 0x00 Priority 0 highDropPrec
3 Bronze_Service Don’t Drop 0x0a Priority 2 lowDropPrec
4 Silver_Service Don’t Drop 0x12 Priority 3 lowDropPrec
5 Gold_Service Don’t Drop 0x1a Priority 4 lowDropPrec
6 Platinum_Service Don’t Drop 0x22 Priority 5 lowDropPrec
7 Premium_Service Don’t Drop 0x2e Priority 6 lowDropPrec
8 Network_Service Don’t Drop 0x30 Priority 7 lowDropPrec
9 Null_Service Don’t Drop ignore ignore lowDropPrec