A bit different of a topic today for me–nothing to do with VMAX! A quick post to give a shout out to a project a few of my colleagues have been working on recently namely, Jim Ruddy (@darth_ruddy) and Ed Walsh (@vEddieW).
Some of you might have read about or maybe even used the Hadoop Starter Kit 1.0 EMC put out around VMworld US earlier this year. For those of you who haven’t heard of it check out some posts here:
As some of you are aware, myself and my colleague Drew Tonnesen (@drewtonnesen) write and update an EMC document called Using EMC Symmetrix Storage in VMware vSphere Environments. This document is what we call a “TechBook”. Essentially a very detailed explanation of the best practices of using VMware with Symmetrix storage as well as overviews of integration points. If you are using Symmetrix and VMware this is a document you should use/know.
Hey all! So as many of you have heard we (EMC) has released the latest version of the Virtual Storage Integrator today (September 16th 2013). There are plenty of blogs/posts that go into all of the details of the new release so I will not regurgitate all of that here. But for those of you who have not seen these posts check them out at these links:
On September 9th EMC released a new SR for Enginuity 5876.251. For the most part this is a variety of fixes and minor enhancements but there is one new hardware feature of note. VMAX has introduced support for 16 Gb FC I/O Modules. So if you have some hosts that are using 16 GB HBAs and want to make full use of them you are gonna want this Enginuity upgrade. Of course you will still have to purchase new front end ports for the VMAX as the current FC ports will not be the correct hardware to support 16 GB.
A common recommendation from storage vendors is to change the default IOPS setting for VMwares’ Native Multi-Pathing (NMP) Path Selection Policy (PSP) Round Robin. The IOPS setting controls how many I/Os are sent down a single logical path before switching to the next path. By default this number is 1,000 I/Os. The VMAX recommendation is to set this to 1. The purpose of this blog post is not to debate the setting, but to help those who want to use it. Regardless, I have seen many customers benefit from this recommendation. Once they see a benefit they want to know–can I make this setting a default?
This is a topic that I get asked about a lot and a recent internal email thread prompted me to write a post about it. On a Symmetrix array if you want a volume larger than 240 GB you need to create a metavolume. When creating a metavolume you have two configuration choices; concatenated or striped. There are many benefits to striped over concatenated (all of them performance-related) but one disadvantage. Due to their nature striped metavolumes are harder to expand. Until a few years ago thin striped metas couldn’t even be expanded online. So the decision was easy–do you think you will need to expand or not. In Enginuity 5875 and Solutions Enabler online expansion of striped metavolumes was allowed.
As you may or may not be aware, I am the sole author of the SRDF Storage Replication Adapter for VMware Site Recovery Manager Techbook. The Techbook for those of you who haven’t used it or aren’t aware of EMC Techbooks is a implementation guide for SRDF with SRM. Best practices, how-to, hints, etc.