Configuring Load-Time Parameters (NSM Procedure)
Load-time parameters include options for tuning IDP performance.
In general, you modify these settings only if you encounter performance
issues.
To configure load-time parameters:
- In NSM Device Manager, double-click the IDP device
for which you want to configure load-time parameters. The device configuration
editor appears.
- Click Sensor Settings.
- Click the Load Time Parameters tab.
- Configure load-time parameters using Table 1.
- Click Apply.
- Click OK.
Table 1: IDP Device Configuration: Load Time Parameters
Setting
|
Description
|
Flow table size (requires sensor restart)
|
For improved IDP performance, set the flow table size
to limit the size of the connection table. This setting should reflect
the maximum number of concurrent flows you expect to have at any one
time. A TCP connection has about two flows per session, and a UDP
connection has about three flows per session. The default setting
is 100,000 concurrent flows. If you change this value, you have to
restart the IDP device.
|
Enable log suppression
|
Log suppression reduces the number of logs displayed
in the Log Viewer by displaying a single record for multiple occurrences
of the same event.
Note:
If the reporting interval is set too high, log suppression
can negatively impact IDP performance.
|
Include destination IP’s while performing log suppression
|
When log suppression is enabled, multiple occurrences
of events with the same source IP, service, and matching attack object
generate a single log record with a count of occurrences. If you enable
this option, log suppression combines log records for events with
the same destination IP.
|
Number of log occurrences after which log suppression
begins
|
This number represents the number of identical log records
received before suppression starts. The default is 1 (meaning log
suppression begins with the first redundancy).
|
Maximum number of logs that log suppression can operate
on
|
When log suppression is enabled, IDP must cache log records
so that it can identify when multiple occurrences of the same event
occur. This number represents the number of log records in the IDP
Management Server that IDP tracks for log suppression. The default
is 16384 log records.
|
Time (seconds) after which suppressed logs will be reported
|
When log suppression is enabled, the IDP device maintains
a count of multiple occurrences of the same event. This number represents
the number of seconds that pass before IDP reports a single log entry
containing the count of occurrences. The default is 10 seconds.
|
Enable application identification
|
The application identification feature is used to detect
the session application regardless of port. We recommend you disable
this feature only when troubleshooting.
|
Maximum number of Application Identification sessions
|
Specifies the maximum number of sessions where application
identification is in use. The default is 1,00,000. Valid values are
0 - 200,000. We recommend you tune this setting only if you encounter
issues.
|
Updated: 2009-05-28