QoS Commands 657User Guidelines• The parametersrefclassname andclass-map-name can not be the same.• Only one other class may be referenced by a class.• Any attempts to delete therefclassname class while the class is stillreferenced by anyclass-map-name fails.• The combined match criteria ofclass-map-name andrefclassname mustbe an allowed combination based on the class type.• Any subsequent changes to therefclassname class match criteria mustmaintain this validity, or the change attempt fails.• The total number of class rules formed by the complete reference classchain (including both predecessor and successor classes) must not exceeda platform-specific maximum. In some cases, each removal of a refclassrule reduces the maximum number of available rules in the class definitionby one.ExampleThe following example adds match conditions defined for the Dell class tothe class currently being configured.console(config-classmap)#match class-map DellThe following example deletes the match conditions defined for the Dellclass from the class currently being configured.console(config-classmap)#no match class-map Dellmatch cosUse the match cos command in Class-Map Configuration mode to add amatch condition for the class of service value (the only tag in a single-taggedpacket or the first or outer 802.1Q tag of a double-VLAN tagged packet).Syntaxmatch cos• cos-value — Specifies the CoS value as an integer (Range: 0–7)Default ConfigurationThis command has no default configuration.
