Sequencer is an engine used by system administrators for the computation and execution of sequences of actions over hardware or software. It can ping various devices in parallel, power on your whole cluster, or generate an Emergency PowerOff (EPO) script for your data center or cluster. It takes into account various dependencies (power off nodes before switches, clients before server), deals with failures kindly, and is very efficient (>4000 nodes in less than 10 minutes).
Open Grid Scheduler/Grid Engine is a batch-queuing system for distributed resource management. It is used by many high-performance clusters and computation farms. Together with basic batch job scheduling, it supports advance reservation, array jobs, parallel make, parallel job management, and GPU management.