Cisco ACI - Interface Policies

For network guys coming from the traditional switching world, the interface configuration on Cisco ACI is not as simple as putting "switchport xxx" command under interface x/x. Rather there is a huge list of interface policies which needs to be configured, which is then referenced in the Interface policy group and then stitched with the actual interface (Interface selector).

The list of interface policies are as follows:

LLDP - Link Layer Discovery Protocol
CDP - Cisco Discovery Protocol
LACP - Link Aggregation Control Protocol
Port Speed
Storm Control
MCP - Mis-Cabling Protocol

Now each policy type is already configured with the default configuration. The best practice is to not touch this default configuration but create an explicit policy.

For example, I always have an LLDP_ON, LLDP_OFF, CDP_ON, CDP_OFF and so on, configured explicitly for my setup.

Explicit policies for each of these policy types also enables you to configure other parameters such as the CDP, LLDP intervals and hold-down timers etc.

More on each of these policy types in detail in the upcoming posts.

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Tejas Jain

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