System availability can be defined on differently depending on the technology layer: Following a bottom up approach, the lowest level of system availability is the existence of the corresponding processes on Operating System layer. Higher on the technology stack is a ping or a dummy login into a system. On application level, there may exist a real business availability check. SAP offers powerful availability checks on all layers.
For general information about monitoring, see Monitoring your SAP NetWeaver Components.
Availability Monitoring with CCMSPING
Availability Monitoring with CCMSPING (SAP Help Portal)
With this function, you can monitor whether remote systems and their instances are available for work from the Alert Monitor of your central monitoring system.
Availability Monitoring and CCMSPING (SAP Tutor)
CCMSPING is a standalone program outside the SAP system with which you can centrally monitor the availability of a large number of components. This SAP Tutor presents an overview of availability monitoring with CCMSPING; from installing the availability agent CCMSPING, through configuring availability monitoring, to displaying the availability data in the Alert Monitor.
With CCMSPING, you can also monitor the availability of components and services by way of RFC destinations and using the SAP NI (Network Interface) library.
Availability Monitoring with GRMG
You can use GRMG Lite to monitor the availability of a URL. No installation on the monitored server is required to do this; instead,m GRMG Lite uses standard capabilities of the HTTP protocol. You can specify which HTTP return codes mean that the URL is available.
Do you want to monitor the availability and the content of URLs centrally? Then why not using the CCMS Monitoring Infrastructure? As of SAP NetWeaver 04 SPS 05, you can monitor a URL by creating a GRMG Lite scenario.
If you want to monitor the availability of technical components and entire business processes centrally, have a look at the Generic Request and Message Generator (GRMG). It is SAP's standard tool for monitoring the availability of web components and Java applications, and it's part of the Monitoring Infrastructure used in the NetWeaver Administrator and the Alert Monitor.