Book Image

Troubleshooting vSphere Storage

By : Mike Preston
Book Image

Troubleshooting vSphere Storage

By: Mike Preston

Overview of this book

Virtualization has created a new role within IT departments everywhere; the vSphere administrator. vSphere administrators have long been managing more than just the hypervisor, they have quickly had to adapt to become a ‘jack of all trades' in organizations. More and more tier 1 workloads are being virtualized, making the infrastructure underneath them all that more important. Due to this, along with the holistic nature of vSphere, administrators are forced to have the know-how on what to do when problems occur.This practical, easy-to-understand guide will give the vSphere administrator the knowledge and skill set they need in order to identify, troubleshoot, and solve issues that relate to storage visibility, storage performance, and storage capacity in a vSphere environment.This book will first give you the fundamental background knowledge of storage and virtualization. From there, you will explore the tools and techniques that you can use to troubleshoot common storage issues in today's data centers. You will learn the steps to take when storage seems slow, or there is limited availability of storage. The book will go over the most common storage transport such as Fibre Channel, iSCSI, and NFS, and explain what to do when you can't see your storage, where to look when your storage is experiencing performance issues, and how to react when you reach capacity. You will also learn about the tools that ESXi contains to help you with this, and how to identify key issues within the many vSphere logfiles.
Table of Contents (16 chapters)
Troubleshooting vSphere Storage
Credits
About the Author
Acknowledgment
About the Reviewers
www.PacktPub.com
Preface
Index

Common storage visibility issues across block transport types


Both Fibre Channel and iSCSI use VMFS-formatted block storage as their data structure. Due to the commonalities of both storage transports, a lot of the steps you can take to troubleshoot connectivity and visibility issues overlap and are explained in the following sections.

ESXi claim rules and LUN masking

As we discussed in Chapter 1, Understanding vSphere Storage Concepts and Methodologies, each storage device managed by vSphere is connected by loading a plugin inside the Pluggable Storage Architecture (PSA). The process inside PSA that associates our storage array devices with the proper storage plugins, whether that is the default NMP provided by VMware or a third-party plugin provided by our storage vendor, is called claiming . Claiming is essentially a group of rules called claim rules that contain associations between the storage devices and either the MPP or the NMP.

So why are claim rules important when it comes to troubleshooting...