QoS - Policing command syntax
When implementing QoS, there are three variants of the policing command found in modern versions of Cisco IOS.
The following three examples show three variants of the police command that achieve the same result. These commands are equivalent.
policy-map policer-cli-example class class-default police 10000000 policy-map policer-cli-example class class-default police cir 10m policy-map policer-cli-example class class-default police rate 10m
The variations have emerged in different Cisco IOS software releases over time and as software trains have merged. Within the same software release, three equivalent variants exist. To avoid backwards compatibility issues, we decided to retain the variants. Please note, however, that the software implementing the policing is identical regardless of the CLI variant used.
Links:
https://www.cisco.com/c/en/us/td/docs/ios/qos/command/reference/qos_book/qos_n1.html#wp1060117