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

Overview of esxtop's interactive commands


There are many different interactive commands that can be run while executing esxtop to help you troubleshoot and identify issues. We can use the following guide to aide us in our esxtop usage.

Activating different displays

esxtop provides us with eight different displays that we can switch to in order to troubleshoot different ESXi components by pressing their corresponding character.

Component

Character

Description

CPU

c

Displays information regarding CPU resource usage

Interrupt

i

Displays information regarding CPU interrupt on VMkernel devices

Memory

m

Displays information regarding memory resource usage

Power management

p

Displays information regarding power usage per CPU

Network

n

Displays information regarding network resource usage

Disk device

u

Displays information regarding usage of disk devices (LUNs/Datastores)

Disk adapter

d

Displays information regarding your disk adapters in the host (HBAs)

Disk VM

v

Displays information regarding the usage of your virtual disks inside the VMs

Field selection

There are many fields available for each view which are not shown by default. To add or remove fields from the display press the F key.

When the field list selection appears, press the corresponding character of the field to toggle whether it is displayed or not.

Field order

Each esxtop display screen has a default order that applies to the statistics it displays. This order can be changed by pressing the O key.

When the field list order screen appears, press the corresponding character of the field to move the field either right or left in the order sequence. Use the uppercase version of a character to move the field left and the lowercase version to move the field right.

Filtering and sorting the displayed objects

We are able to filter the objects (worlds) that esxtop displays in many different ways.

  • To filter or limit display by a single group, press L, type the corresponding world/group ID and hit Enter. To remove filter press L and Enter.

  • To view only instances related to VMs, press V. Pressing V again will restore all worlds.

  • To view only a certain number of results press #, enter the desired number and press Enter. Using 0 as the desired number will display all results.

  • On certain views you are able to expand or rollup statistics as they are shown as aggregated data by default. To do so, press E and enter the desired data to expand/rollup.

  • To sort by certain columns, press H to enter the help screen. Under the Sort by: section, make a note of the desired column to sort by. Press any key to return to the main statistics screen and press the desired character of the column to sort.

Other useful information

The following bullet points outline some other useful commands and switches that esxtop contains:

  • To change the default refresh level, press S and enter the desired refresh interval in seconds.

  • To save your current configuration of column orders, sort fields, and so on, press W and enter a filename.

  • To load esxtop and apply a configuration file, start esxtop with the –c <configfile> option.

  • esxtop can also be run in batch mode which will capture results to a CSV file. This is done by specifying –b when starting esxtop and output to a filename.

  • There are many different command line options you can also pass when running esxtop in batch mode. For a complete list, run esxtop –h.

    Tip

    VMware has an application available for download that allows you to view esxtop from within a GUI interface called Visual esxtop. For more information, visit http://labs.vmware.com/flings/visualesxtop.