A Nagios Plugin written in Perl for the Citrix NetScaler. It's based on the the NITRO API.


check_netscaler Nagios Plugin

A Nagios Plugin written for the Citrix NetScaler Application Delivery Controller. It's based on Perl (Nagios::Plugin) and using the the NITRO REST API. No need for SNMP.

Currently the plugin has the following subcommands:

  • state: check the current service state of vservers (e.g. lb, vpn, gslb), services and service groups
  • string, string_not: check if a string exists in the api response or not (e.g. HA or cluster status)
  • above, below: check if a value is above/below a threshold (e.g. traffic limits, concurrent connections)
  • sslcert: check the lifetime for installed ssl certificates
  • nsconfig: check for configuration changes which are not saved to disk
  • staservers: check if configured STA servers are available
  • debug: debug command, print all data for a endpoint

This plugin works with VPX, MPX and SDX NetScaler Appliances. The api responses may differ by build, appliance type and your installed license.

The plugin supports performance data for the commands state and the above or below threshold checks.

Feedback and feature requests are appreciated.


On a Enterprise Linux machine (CentOS, RHEL) execute the following commands to install all Perl dependencies (Nagios::Plugin, LWP, JSON):

yum install perl-libwww-perl perl-JSON perl-Nagios-Plugin

If you want to connect to your NetScaler with SSL/HTTPS you should also install the LWP HTTPS package.

yum install perl-LWP-Protocol-https

Usage Examples

Check status of vServers

# NetScaler::LBvServer
./check_netscaler.pl -H ${IPADDR} -s -C state -o lbvserver

# NetScaler::LBvServer::Website
./check_netscaler.pl -H ${IPADDR} -s -C state -o lbvserver -n vs_lb_http_webserver

# NetScaler::VPNvServer
./check_netscaler.pl -H ${IPADDR} -s -C state -o vpnvserver

# NetScaler::GSLBvServer
./check_netscaler.pl -H ${IPADDR} -s -C state -o gslbvserver

# NetScaler::AAAvServer
./check_netscaler.pl -H ${IPADDR} -s -C state -o authenticationvserver

# NetScaler::CSvServer
./check_netscaler.pl -H ${IPADDR} -s -C state -o csvserver

# NetScaler::SSLvServer (obsolet and replaced by lbvserver for newer builds)
./check_netscaler.pl -H ${IPADDR} -s -C state -o sslvserver

Check status of services

# NetScaler::Services
./check_netscaler.pl -H ${IPADDR} -s -C state -o service

# NetScaler::Services::Webserver
./check_netscaler.pl -H ${IPADDR} -s -C state -o service -n svc_webserver

Check status of servicegroups

# NetScaler::Servicegroups
./check_netscaler.pl -H ${IPADDR} -s -C state -o servicegroup

# NetScaler::Servicegroups::Webservers
./check_netscaler.pl -H ${IPADDR} -s -C state -o servicegroup -n sg_webservers

Check system health

# NetScaler::Memory
./check_netscaler.pl -H ${IPADDR} -s -C above -o system -n memusagepcnt -w 75 -c 80

# NetScaler::CPU
./check_netscaler.pl -H ${IPADDR} -s -C above -o system -n cpuusagepcnt -w 75 -c 80

# NetScaler::CPUMGMT
./check_netscaler.pl -H ${IPADDR} -s -C above -o system -n mgmtcpuusagepcnt -w 75 -c 80

# NetScaler::Disk0
./check_netscaler.pl -H ${IPADDR} -s -C above -o system -n disk0perusage -w 75 -c 80

# NetScaler::Disk1
./check_netscaler.pl -H ${IPADDR} -s -C above -o system -n disk1perusage -w 75 -c 80

Check high availability status

# NetScaler::HA::Status
./check_netscaler.pl -H ${IPADDR} -s -C string_not -o hanode -n hacurstatus -w YES -c YES

# NetScaler::HA::State
./check_netscaler.pl -H ${IPADDR} -s -C string_not -o hanode -n hacurstate -w UP -c UP

Check expiration of installed ssl certificates

# NetScaler::Certs
./check_netscaler.pl -H ${IPADDR} -s -C sslcert -w 30 -c 10

# NetScaler::Certs::Wildcard
./check_netscaler.pl -H ${IPADDR} -s -C sslcert -n wildcard.example.com -w 30 -c 10

Check for unsaved configuration changes

# NetScaler::Config
./check_netscaler.pl -H ${IPADDR} -s -C nsconfig

Check if STA servers are working

# NetScaler::STA
./check_netscaler.pl -H ${IPADDR} -s -C staservers

# NetScaler::STA
./check_netscaler.pl -H ${IPADDR} -s -C staservers -n vs_vpn_gateway

Debug command

# Print all LB vServers (stat endpoint)
./check_netscaler.pl -H ${IPADDR} -s -C debug -o lbvserver

# Print all LB vServers (config endpoint)
./check_netscaler.pl -H ${IPADDR} -s -C debug -o lbvserver -e config

Configuration File

The plugin uses the Nagios::Plugin Libary, so you can use --extra-opts and seperate the login crendetials from your nagios configuration.


define command {
  command_name check_netscaler_vserver
  command_line $USER5$/3rdparty/check_netscaler/check_netscaler.pl -H $HOSTADDRESS$ --extra-opts=netscaler@$USER11$/plugins.ini -C check_vserver -I '$ARG1$'

NITRO API Documentation

You will find a full documentation about the NITRO API on your NetScaler Appliance in the "Download" area.

http://NSIP/nitro-rest.tgz (where NSIP is the IP address of your NetScaler appliance).

Tested Firmware

Tested with NetScaler 10.5, 11.0 and 11.1. The plugin should work with all available releases.