140 Appendix C. ProbesField ValueSendExpectTimeout* 10Critical Maximum LatencyWarning Maximum LatencyTable C-13. General::UDP Check settingsC.4.6. General::Uptime (SNMP)The General::Uptime (SNMP) probe records the time since the device was last started. It uses theSNMP object identifier (OID) to obtain this value. The only error status it will return is UNKNOWN.Requirements — SNMP must be running on the monitored system and access to the OID must beenabled to perform this probe.This probe’s transport protocol is User Datagram Protocol (UDP).Field ValueSNMP Community String* publicSNMP Port* 161SNMP Version* 2Timeout* 15Table C-14. General::Uptime (SNMP) settingsC.5. LinuxThe probes in this section monitor essential aspects of your Linux systems, from CPU usage to virtualmemory. Apply them to mission-critical systems to obtain warnings prior to failure.Unlike other probe groups, which may contain one or a few probes that require the Red Hat NetworkMonitoring Daemon, every Linux probe needs rhnmd to be running on the monitored system.C.5.1. Linux::CPU UsageThe Linux::CPU Usage probe monitors the CPU utilization on a system and collects the followingmetric:• CPU Percent Used — The five-second average of the percent of CPU usage at probe execution.Requirements — The Red Hat Network Monitoring Daemon (rhnmd) must be running on the moni-tored system to run this probe.Field Value
