Information About Customizing a Built-in Protocol
Customizing Built-in Protocols
Each built-in NBAR2 protocol (provided by the Cisco Protocol Pack) is pre-configured to recognize traffic of a specific type of network application. In some situations, it can be useful to “customize” a protocol, adding to the scope of traffic that it matches and recognizes. This is accomplished by configuring user-specified domains that extend the scope of the protocol. Each customization is identified by a user-supplied name.
For example, the built-in office365 protocol matches Microsoft Office 365 application traffic. Customizing the office365 protocol by adding additional domains can extend its scope.
Visibility and Control
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Application visibility: Traffic that matches the user-specified extension of the built-in protocol is reported by the name of the user-specified customization.
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Application control: After extending a built-in protocol, any policy associated with the protocol applies also to the user-specified domain.
Usage Notes
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The maximum number of customizations is 120. This count includes other types of customization.
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Customizing a protocol does not change its priority.
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The custom-name of a customization cannot be used for defining policy.
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It is possible to configure multiple domains for the same custom-name . Example:
ip nbar custom myOffice365 dns domain-name "*uniqueOffice365" extends office365 ip nbar custom myOffice365 dns domain-name "*anotherUniqueOffice365" extends office365
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Multiple customization commands can extend the same built-in protocol. Example:
ip nbar custom myOffice365_D1 dns domain-name "*uniqueOffice365" extends office365 ip nbar custom myOffice365_D2 dns domain-name "*anotherUniqueOffice365" extends office365