Oracle Clusterware (on Unix/Linux) is now started through a single entry in init. This starts the OHASD (Oracle High Availability Services Daemon), which is responsible for starting the rest if the background processes. New background processes with 11g Release 2 (defined in the Oracle Clusterware Admin and Deployment Guide) are:
CRSCTL, the command line interface for managing the cluster, introduces a clusterized start or stop of the cluster. From any node in the cluster, you can enter crsctl stop cluster -all and the clusterware will be stopped on all nodes. Note: Not all background processes will be stopped, you will still see OHASD, MDNSD, and GPNPD running. To start the cluster, enter crsctl start cluster -all and the clusterware will be started on all nodes. This is achieved through the OHASD. If you want all Oracle Clusterware processes stopped, you can use the command crsctl stop crs.
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