Storage Basics – Part VII: Storage Alignment

At the risk of beating a dead horse, it's time to resurrect my Storage Basics series.  I've recently had some great feedback on the series and figured I should round out a few of the concepts before I wrap it up.  I want to cover a topic often discussed amongst virtualization professionals, but one I often find general practitioners and server admins not understanding: storage alignment.  Storage alignment, or the lack of alignment, is not a new issue and is not unique to VMware or virtualization in general.  However, the effects of misaligned storage can be more greatly felt in terms of … [Read more...]

Storage Basics – Part V: Controllers, Cache and Coalescing

My Storage Basics series has been neglected for some time (sick kids, snow storms, VMware Upgrades, SAN implementations and some Cisco switch upgrades took all my free time), so let's jump right in to Part V - Cache, Controllers, and Coalescing.   Between the alliteration and fancy words, it might seem like I am about to tell a tale of international espionage.  Unfortunately, my introductory treatment of these aspects of a storage system will probably not keep you on the edge of your seat - but I'll try to keep it interesting. Throughout this series, we've been working our way from the … [Read more...]

Storage Basics – Part III: RAID

This is the third in a multi-part series on storage basics.  I've had some good feedback from folks in the SMB space saying that the first couple posts in this series have been beneficial, so we'll be sticking with some basic concepts for another post or two before we dive into some nitty-gritty details and practical applications of these concepts in a VMware environment.  In the second post of this series I introduced the concept of IOPS and explained how the physical characteristics of a hard disk drive determine the theoretical IOPS capability of a disk.  I then noted that you can aggregate … [Read more...]

The Skinny on ESXTOP

A reader named Mark contacted me today and asked if there was a way to reduce the size of the batch output from an ESXTOP run.  And he asks for good reason: Depending on the number of VM's on your host, the delay between ESXTOP samplings and the number of samples you collect, using the All Stats option (-a) can yield a massive file in a short period of time.  If written to a partition on your ESX Service Console you run the risk of filling the partition, and forget about actually being able to analyze the data in PERFMON or Excel.  For example, on an ESX host running ~15 VM's I produced 100MB … [Read more...]

Virtualization Bookmarks for August 28th

Here are some bookmarks for resources that I have recently referenced: vCenter 4 and ESX 4 Now Use 10 Year Default SSL Certificate | VM /ETC - Rich Brambly has some guidance on installing a new SSL certificate on vCenter, with very useful links in his post to official VMware documentation and KB's on the subject. VMware vSphere Client on Microsoft Windows 7! | Virtual Lifestyle - Heiko Verlande has found a way to run the VMware vSphere Client on Windows 7. Virtu-Al » PowerCLI: Daily Report V2 - Version two of a handy PowerShell based VMware Environment Daily Report from VMware vExpert … [Read more...]