Set Global Preferences

You can configure global settings that affect the way data is automatically collected, stored, and forwarded, such as the following settings:

The number of hours to retain packet capture files.
The frequency of automatic database maintenance.
Whether packet deduplication is enabled.

In most cases, the default settings are appropriate. However, you can change the settings to ensure the optimal functioning of your system.

Follow these steps:

Click Administration, Application Settings in the web interface. The Application Settings page opens.
Complete the following fields:
- Perform automatic file maintenance every. The number of minutes between automatic file maintenance operations. If necessary, the oldest raw packet capture files are deleted during maintenance. This setting determines the frequency of capture file deletion. The default is 5. If you change this setting, restart the nqmaintd process. The threshold for removing raw packets also affects the frequency of file deletion.
- When disk space usage is normal, keep raw packet capture files for. The length of time raw packet capture files are stored before being automatically deleted. These files are continually generated during ordinary monitoring. The default is 6. If you change this setting, restart the nqmaintd process.
- Automatically remove raw packet capture files older than one hour when disk utilization reaches. The maximum percentage of disk space that can be in use before raw packet capture files older than one hour are automatically purged. The automatic file maintenance interval also affects the frequency of file deletion. The default is 80 percent. This threshold does not apply to packet capture investigation files. If you change this setting, restart the nqmaintd process.
- Keep Application Delivery Analysis packet capture investigation files for. The number of days that packet capture investigation files are stored before being automatically deleted. These files are generated in response to a packet capture investigation request from CA Application Delivery Analysis. Packet capture investigation files are stored separately from raw capture files. This threshold does not apply to raw packet capture files. The default is 90. If you change this setting, restart the nqmaintd process.
- Keep one-minute session metrics for. The number of days that metric data taken from captured packets are kept in the Multi-Port Monitor database. The default is 7. An internal maximum threshold is applied to this database. Data from fewer than the selected number of days is kept when the number of rows in the database exceeds 12 billion rows. If the threshold is exceeded, the oldest data is discarded first.
- Perform packet deduplication. When enabled, Multi-Port Monitor attempts to filter out duplicate packets that can be received from mirrored ports. By default, deduplication is enabled. The System Status page tracks the number of packets that the capture card discarded. If you change this setting, restart the nqcapd process.
- Encrypt raw packet capture files on disk. When enabled, raw packet capture files are saved in encrypted format on the Multi-Port Monitor hard disk. By default, these files contain only the header information of all traffic captured. But they can contain payload data when packet slicing options are changed to retain more of the packet. Packet capture investigation files, which are filtered to contain information from a single server, are not encrypted. Encryption is processor-intensive. Enabling this option can degrade the ability of the monitoring device to save packet capture files. A unique key for the encryption is created when you first start Multi-Port Monitor. The key is not changed thereafter. If you change this setting, restart the nqcapd process.
Click Save. The Application Settings page is refreshed with your changes.
Restart the nqmaintd process or the nqcapd process if necessary.

More information:

Packet Deduplication

Capture Card Physical Port Statistics

Stop or Restart a Process

What is Packet Slicing?

Purge Data from the Database