Add Class to QoS Policy Window
This
window appears when you click Add Class in the Create QoS Policy window.
Use it to:
When you complete these tasks, click OK.
-
In the Classes list, select a class (if one has been defined) or Define
Class.
If you select an existing class
, the fields in the Class Definition box are filled in for you, and
this task is complete.
If you select Define Class
, continue to the next step.
-
In the Class Name field, enter a unique name for the class.
-
Optional: In the Description field, enter text that describes
the purpose of the class.
- If this class is for a Catalyst 2950 switch, go to Step 8.
-
In the Match list, select the packet characteristic
DSCP
values, IP precedence values, or an ACL name
that
is special to this class.
When you choose a characteristic, a corresponding field in the window is enabled,
allowing you to be more specific.
- If you chose DSCP from the Match list,
e
nter one or mor
e DSCP v
alues in the DSCP field. Use spaces to separate multiple values.
- If you chose IP Precedence from the Match list,
e
nter one or mor
e IP precedence v
alues in the IP Precedence field. Use spaces to separate multiple values.
- If you chose ACL from the Match list or if the class is for
a Catalyst 2950 switch,
s
elect the ACL name that the class matches from the ACL list.
To override values in matching packets:
- Click the Set tab.
- From the Type list, select DSCP
if you want to override the DSCP values. Otherwise, select None.
- If you chose DSCP, enter
the DSCP override value in the DSCP field.
To override values in matching packets:
- Click the Set/Trust tab.
- Click the Set radio button to enable the Set section.
- From the Type list, select DSCP
or IP Precedence if you want to override the DSCP values, IP precedence
values, or ACL name in matching packets with a single DSCP value or IP precedence
value. Otherwise, select None.
Note: You can override DSCP values with an IP precedence value or IP
precedence values with a DSCP value.
- If you chose DSCP, enter
the DSCP override value in the DSCP field.
- If you chose IP Precedence, enter
the IP precedence override value in the IP Precedence field.
To trust values in matching packets:
- Click the Set/Trust tab.
- Click the Trust radio button to enable the Trust section.
- From the Trust Type list, select Trust
CoS, Trust DSCP, or Trust IP Precedence if you want to trust
the CoS, DSCP, or IP precedence value of packets that belong to this class.
Otherwise, select Not Trusted.
- Click the Policer tab.
-
In the Policers list, select an aggregate
policer (if one has been defined), Define Policer, or No Policer.
If you select an aggregate policer
, the fields in the Policer Definition box are filled in for you, and
this task is complete.
If you select Define Policer
, continue to the next step.
If you select No Policer
, ignore the remaining steps. N
o policing is associated with the class.
-
In the Policer Name field, enter a name for the policer if you want
it to be an aggregate policer. Otherwise, leave this field blank.
Restriction: This option is not supported on Catalyst 2950 switches.
Specifying a nonaggregate policer
see
the following steps
is supported
on these switches if they run the enhanced software
image.
-
In the Rate [kbps] field, enter the maximum transmission rate that
you will permit on the interface. The number that you enter is the rate in
kilobits per second. You can enter a value between 8 and 2000000, inclusive
on the Catalyst 3550 switches. On the Catalyst 2950 switches, you can enter
a value from 1000 to 1000000, in multiples of 1000.
-
In the Max Burst Size [KB] field, enter the maximum burst size that
you will permit on the interface. The number that you enter is the size in
kilobytes. You can enter a value between 8 and 512000, inclusive on the Catalyst
3550 switches. On the Catalyst 2950 switches, the MAX Burst column has a drop-down
menu of choices.
-
In the Exceed Action list, select an action you want to occur if either
maximum is exceeded. Selecting Drop causes the policer to drop a packet
in violation. Selecting Police DSCP and Transmit causes the policer
to modify the DSCP value and transmit the packet. Selecting None causes
the policer to take no action.
-
If you selected Police DSCP and Transmit, s
elect a DSCP value from the Policed DSCP field that the policer will
give to a packet in violation.
Note: This field is available only for Catalyst 2950 switches. For
Catalyst 3550 switches, the policer uses the DSCP value it finds in the
Policed DSCP Table.