Netflow Tools «POPULAR»

| Symptom | Likely Cause | Fix | |---------|--------------|-----| | No flows received | ACL blocking UDP 2055 | show access-list | | Flows show 0 bytes | Sampling rate too high | Reduce sampling-rate | | AS numbers are 0 | BGP table not loaded | ip flow-export bgp-nexthop | | Timestamps wrong | NTP drift | ntp peer on exporter | | High CPU on router | Flow cache too large | ip flow-cache entries 65536 |

A production NetFlow deployment has :

Popular collectors:

interface GigabitEthernet0/1 ip flow ingress ip flow egress ! ip flow-export source Loopback0 ip flow-export version 5 ip flow-export destination 192.168.1.100 2055 netflow tools