Select a Citrix NetScaler SDX/MAS (Management and Analytics System) appliance as the target host to create a monitor — the SNMP service should be up and running on it. Click New Monitor, then check SNMP Custom on the Favorites tab, click Next, and confirm the host. On the next page, click Select... to open the built-in SNMP MIB Browser and locate systemCurrentTime under the systemGroup branch of MIB, then select it and click OK. It reports the appliance's current system time. On the monitor's Main parameters page you can set the target's SNMP port (default 161), credentials, polling interval, and other settings — see the SNMP Monitor help for details. On the State conditions and Alerting tabs, configure when the monitor should change state and trigger an alert; since this is an Integer32-type OID, Value bounds is the most useful condition here — trigger an alert if this value drifts noticeably from your reference/NTP time, which would indicate a clock-synchronization problem on the appliance. Click Finish to create the monitor; you can adjust any parameter later.