Cloud monitoring is an undertaking that helps to maintain applications active and perform constantly well. Cloud monitoring services collect a range of information about applications’ performance, storage, servers and networks within a provider’s ecosystem. A well-designed monitoring infrastructure, which does the aforementioned prerequisites, must be scalable and support various important performance parameters. Cloud monitoring is essential for both cloud users and providers. Along with, it is a central tool for managing software and hardware infrastructure. Moreover, it furnishes information and key performance indicators for cloud layer services. In cloud computing, monitoring has two types namely high-level and low-level monitoring. The high-level monitoring is for virtual platform status while the low level is related to the physical infrastructure. Furthermore, two types of cloud network monitoring are underlay and overlay. In this paper, the authors present a comprehensive survey and discussion in respect of high level, low level, underlay and overlay cloud monitoring. A generalize metric grouping for high level, low level, underlay, and overlay cloud monitoring were established. 

Keywords: Cloud, High Level, Low Level, Metrics, Monitoring, Overlay, Underlay