Routing control functions (RCF) is a new language, a different way of policy definition and application in a programmatic fashion (https://www.arista.com/en/support/toi/eos-4-27-2f/15102-routing-control-functions-language-and-configuration). EOS Application Programmable Interface (eAPI) is another means whereby commands are sent to the switch (i.e. aside from the switch’s command-line interface - CLI which has been the norm), which can be executed through various methods like web interface, shell or a program/script.

Some monitoring tools have a limited time to receive information from the switch and may break if waiting for a

Eapi 4.21.3F