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Another important aspect of the new routing configuration is Routing Instancethe global Router ID, which sets router-id and group peers in one instance. RouterOS adds a default instance ID which picks instance-id from any interface's highest IP. The default BGP template by default is set to use the "default" instanceID.
If for any reason you need to tweak or add new instances it can be done in /routing instanceid menu.
Very interesting parameters are input.affinity andoutput.affinity, they allow control in which process input and output of active session will be processed:
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