The destination command is required to complete the flow record and specify the IP address of the Stealthwatch collector that will receive the NetFlow data. The transport udp 2055 command is also needed, but it is part of the flow exporter configuration, not the flow record. The match ipv4 ttl and cache timeout active 60 commands are optional and can be used to customize the flow record, but they are not mandatory.
The flow record defines the fields that are collected and exported for each flow, such as source and destination IP addresses, ports, protocols, etc. The flow exporter defines the destination, source, transport protocol, and port for sending the NetFlow data. The flow monitor binds the flow record and the flow exporter together and applies them to an interface. The following is an example of a complete NetFlow configuration for sending data to Stealthwatch:
flow exporter EXPORTER description Export NetFlow to Stealthwatch destination 1.1.1.1 export-protocol netflow-v9 source Vlan100 transport udp 2055 ! flow record RECORD description NetFlow record match datalink mac source address input match datalink mac destination address input match datalink vlan input match ipv4 ttl match ipv4 tos match ipv4 protocol match ipv4 source address match ipv4 destination address match transport source-port match transport destination-port match interface input collect interface output collect counter bytes long collect counter packets long collect timestamp absolute first collect timestamp absolute last ! flow monitor IPv4_NETFLOW record RECORD exporter EXPORTER cache timeout active
60 ! interface <> ip flow monitor IPv4_NETFLOW input ! References : Configuring and Troubleshooting NetFlow for Stealthwatch, Cisco NetFlow Configuration, Building a Better Monitoring Solution with Flexible Netflow