Configuring SNMP Alarms for rate limiting

Last published : Sep 24, 2026
NetScaler appliances are rate limited. For information about the different models available for each platform, see the data sheet. The data sheet is available on www.citrix.com. Click Products. Under App Delivery and Security, click NetScaler. Click Platforms > Physical appliances and then click NetScaler MPX/SDX data sheet.
The maximum throughput (in percentage) and packets per second (PPS) are determined by the license purchased for the appliance. For rate-limited platforms, you can configure SNMP traps to send notifications when throughput and PPS approach their limits and when they return to normal.
Throughput and PPS are monitored every seven seconds. You can configure traps with high-threshold and normal-threshold values, which are expressed as a percentage of the licensed limits. The appliance then generates a trap when throughput or PPS exceeds the high threshold, and a second trap when the monitored parameter falls to the normal threshold. In addition to sending the traps to the configured destination device, the NetScaler appliance logs the events associated with the traps in the /var/log/ns.log file as EVENT ALERTSTARTED and EVENT ALERTENDED.
Exceeding the throughput limit can result in packet loss. You can configure SNMP alarms to report packet loss.
For more information about SNMP alarms and traps, see "Configuring the NetScaler to generate SNMP v1 and v2 Traps."
This document includes the following details:
  • Configuring an SNMP alarm for throughput or PPS
  • Configuring an SNMP alarm for dropped packets
Related information

Configuring an SNMP alarm for throughput or PPS

To monitor both throughput and PPS, you must configure separate alarms and set the threshold and PPS value.

To configure an SNMP alarm for the throughput rate by using the CLI

At the command prompt, type the following commands to configure the SNMP alarm, set threshold value (in percentage) and verify the configuration:
  • set snmp alarm PF-RL-RATE-THRESHOLD [-thresholdValue <positive_integer> [-normalValue <positive_integer>]] [-state ( ENABLED | DISABLED )] [-severity <severity>] [-logging ( ENABLED | DISABLED )]
  • show snmp alarm PF-RL-RATE-THRESHOLD

Example

> set snmp alarm PF-RL-RATE-THRESHOLD -thresholdValue 70 -normalValue 50

To configure an SNMP alarm for PPS by using the CLI

At the command prompt, type the following commands to configure the SNMP alarm for PPS and verify the configuration:
  • set snmp alarm PF-RL-PPS-THRESHOLD [-thresholdValue <positive_integer> [-normalValue <positive_integer>]] [-state ( ENABLED | DISABLED )] [-severity <severity>] [-logging ( ENABLED | DISABLED )]
  • show snmp alarm PF-RL-PPS-THRESHOLD

Example

> set snmp alarm PF-RL-PPS-THRESHOLD -thresholdValue 70 -normalValue 50

To configure an SNMP alarm for throughput or PPS by using the GUI

  1. Navigate to System > SNMP > Alarms, and select PF-RL-RATE-THRESHOLD (for throughput rate) or PF-RL-PPS-THRESHOLD (for packets per second).
  2. Set the alarm parameters and enable the selected SNMP alarm.

Configuring SNMP alarm for dropped packets

You can configure an alarm for packets dropped as a result of exceeding the throughput limit and an alarm for packets dropped as a result of exceeding the PPS limit.

To configure an SNMP alarm for packets dropped because of excessive throughput by using the CLI

At the command prompt, type:
set snmp alarm PF-RL-RATE-PKTS-DROPPED [-state (ENABLED | DISABLED)] [-severity <severity>] [-logging ( ENABLED | DISABLED )]

To configure an SNMP alarm for packets dropped because of excessive PPS by using the CLI

At the command prompt, type:
set snmp alarm PF-RL-PPS-PKTS-DROPPED [-state (ENABLED | DISABLED)] [-severity <severity>] [-logging ( ENABLED | DISABLED )]

To configure an SNMP alarm for dropped packets by using the GUI

  1. Navigate to System > SNMP > Alarms, and select PF-RL-RATE-PKTS-DROPPED (for packets dropped because of excessive throughput) or PF-RL-PPS-PKTS-DROPPED (for packets dropped because of excessive PPS).
  2. Set the alarm parameters and enable the selected SNMP alarm.