Recently I was extended an opportunity to read and review “Troubleshooting vSphere Storage” by my friend, Mike Preston (@mwpreston | blog.mwpreston.net). [Amazon | Packt Publishing]
This book is based on vSphere 5.1 and only covers those features and the functionality available in the 5.1 thick client. (Personally, I felt the 5.1 web client was…full of opportunities for improvement), but the lack of web client related information doesn’t detract at all from the depth of technical knowledge that’s packed into this book. It weighs in at about 127 pages + index, and spares no time in jumping right in.
It’s divided into chapters that build on each other in a logical fashion. The first chapter claims to communicate a basic understanding of vSphere storage concepts, but certainly isn’t level 101 material. The chapter dives into the different ways that vSphere identifies and tracks storage, namely: naa, T10, IQN, and MPX. From there it moves to PSA/PSP and details the lifecycle of a storage I/O request.
Additional chapters include:
- Common tools for troubleshooting storage, such as the vCenter client storage maps, esxtop/resxtop, and the various logfiles and locations for each piece of a vSphere infrastructure.
- Troubleshooting Fibre Channel and IP storage visibility
- Claim rules, path selection, disk resignaturing
- Troubleshooting storage contention
- Monitoring different types of latency with esxcli, leveraging vCenter alarms, understanding and architecting according to IOPs requirements, Storage DRS and Storage IO Control (SIOC)
- Troubleshooting capacity and overcommitment
- Thin provisioning, snapshots, swap files, and extents
- Troubleshooting by use case
- Example: The use case titled “You cannot connect to your iSCSI storage” includes the list of things to troubleshoot, and the necessary steps to remediate the problems.
- esxtop’s different displays, commands, and storage related statistics
- iSCSI error codes
- A list of iSCSI error codes as displayed in vSphere’s logfiles
I really enjoyed the level of detail in this book, and it’s my opinion that this would be a valuable resource to vSphere administrators at all levels of expertise. My favorite section is Appendix A, which details the different storage related use cases and how to fix each problem.
I reviewed both the VCP5-DV and VCAP5-DCA blueprints, and this book is a great resource for each exam. Admittedly, it’s been a long time since I took the VCP5-DV, and while the style of exam is different from the DCA (multiple choice vs. performing administrative actions in a live lab), it should be valuable to those pursuing either/both exams, especially the DCA. Additionally, it’s a good resource for those planning for their VCDX certifications as there’s a live troubleshooting portion of the VCDX defense, and based on what I’ve heard from folks like John Arrasjid (@vcdx001), storage concerns are very much in scope.
Overall, I highly recommend this book for vSphere administrators looking to learn more about the environment they’re supporting, and for folks that are pursuing various levels of vSphere certifications.