NetFlow FAQ & Troubleshooting
Troubleshoot ISPBills NetFlow collection, versions, ports, retention, trials, exports and sampled flow settings.
Use these answers to resolve common NetFlow collection, trial, access and exporter configuration issues in ISPBills.
For first-time configuration, follow the setup guide before troubleshooting individual exporters.
FAQ
Why am I not seeing any flows after enabling the collector?
Confirm the router exports to the exact collector IP and UDP port shown in Settings → NetFlow or Monitoring → NetFlow. Check firewall rules, NAT translation, router time, exporter status and whether the Sources or Live Flows panel shows a recent last-seen timestamp.
Which NetFlow versions does ISPBills support?
ISPBills supports NetFlow v5, NetFlow v9 and IPFIX. sFlow is not supported directly; use an sFlow-to-NetFlow or sFlow-to-IPFIX converter before sending records to ISPBills.
How long is flow data retained?
Retention depends on your subscription and storage policy. Trial data is retained for 30 days after the trial expires, while active add-on data follows the retention settings shown in the NetFlow dashboard or subscription terms.
Does NetFlow slow down my routers?
NetFlow has a resource cost because routers must summarise and export flow records. Most modern routers handle it well, but busy edge and core devices should use sampling, shorter active timeouts and interface-specific export to optimise behaviour.
Can I export flow data?
Yes. Operators with the required admin, group_admin or noc permissions can export available reports from the NetFlow dashboard when export actions are enabled for their role.
What ports does ISPBills listen on?
Use the UDP port shown in Settings → NetFlow or Monitoring → NetFlow for your account. Common deployments use UDP 2055, 2056 or 9995, but the portal value is authoritative.
Why does the trial not appear on my account?
The trial is available only for eligible Mid-tier or Large-tier accounts. A super_admin must also enable add-on visibility for your organisation before NetFlow appears under Account → Plans → Add-ons.
Will my customers see NetFlow data?
No. NetFlow data is visible only to authorised admin, group_admin and noc roles. Customer self-service users do not see traffic analysis, source lists or live flow records.
How do I configure sampled NetFlow?
Set the sampling ratio on the exporter and enter or document the same ratio in ISPBills where the source settings request it. Start with 1:100 to 1:500 for Mid-tier aggregation and 1:500 to 1:2000 for Large-tier core links, then adjust after comparing reports with interface counters.
Quick Troubleshooting Checklist
| Symptom | Check |
|---|---|
| No source appears | Collector IP, UDP port, firewall and route from exporter |
| Source appears but no graphs | Flow version, templates, sampling ratio and time range |
| Incorrect traffic totals | Sampling mismatch or missing ingress/egress interface export |
| Trial button missing | Mid or Large tier eligibility and super_admin add-on visibility |
If the issue remains unresolved, open Support → Ticket and include the exporter model, flow version, collector port, source IP and a screenshot of the NetFlow source status.