PRTG NetFlow Analyzer is Paessler's powerful network monitoring utility. It ensures the availability of network components while also measuring net bandwidth, monitoring network utilization and load. It saves costs by avoiding outages, optimizing connections, saving time and controlling service level agreements (SLAs). PRTG has been tested and certified "Cisco Compatible" as it is a market leading tool for network monitoring and is able to analyse Cisco's NetFlow protocol. You can use as many NetFlow sensors as you want with any PRTG license, they just count against your overall sensor limit.
Monitoring Cisco ASA with Netflow 9
Monitor Cisco ASA Firewalls with PRTG
Netflow is a protocol developed by Cisco for collecting IP traffic information which gives network administrators useful information on bandwidth usage, types of traffic, or traffic volume. Recently Cisco has implemented NetFlow 9 for its popular ASA 5500 security and firewall appliances. But this implementation of Cisco ASA NetFlow is quite different from what other Cisco devices provide. It is called "Netflow Security Event Logging" (NSEL) and was originally introduced with the Cisco ASA 5580. Now, with the latest firmware (ASA 8.2.x or later), it has also been extended to other Cisco ASA models.
How does Cisco ASA NetFlow Monitoring Work?
Although Cisco ASA Netflow 9 was not created for real-time traffic analysis (but for security events monitoring) it can be used for bandwidth monitoring. In combination with PRTG Network Monitor, Cisco ASA Netflow 9 offers the following features:
- Monitoring of bandwidth usage
- Top Connections
- Top Talkers
- Top Protocols
It must be noted that Cisco ASA Netflow 9 faces some limitations when compared to the normal Netflow protocol:
- Traffic data is not shown in real time, but only after the connection has ended. This results in an uneven distribution of traffic data for long connections
- Incoming and outgoing traffic data are shown together, with no distinction between the two directions
- Netflow 9 monitoring on the Cisco ASA causes a considerable CPU load
