Core issue
This issue is due to the presence of Cisco bug ID CSCsc92316 and occurs most often in the Intrusion Prevention System (IPS) version 5.1(1).
The IPS almost always encounters this issue when these conditions are met:
- Bypass mode is enabled, for example, Auto_on.
- The SensorApp fails to respond to control transaction (CT) requests and so the Error: getAnalysisEngineStatistics : Control transaction cannot be completed at this time error message appears.
- The SensorApp appears to run in the top, and the processes system (PS) output, memory and CPU percentage appear normal. There are no core.txt files for sensorApp or old core.txt files.
- The Cids-shared.info shows zero free buffers, for example, Free Buffers 0 (0%), but this is not always the case. For example, it can also show 80 percent FreeBuffers.
Resolution
The temporary workaround for this issue is to reboot the sensor.
In order to completely resolve this issue, upgrade the IPS to version 5.1(2) or later. Refer to Cisco Downloads in order to download the latest software version.
Refer to the Upgrading the Sensor section of Upgrading, Downgrading, and Installing System Images in IPS.