Posts

In my last post I explained a memory reclamation technique called Transparent Page Sharing. This post is dedicated to the Balloon driver method. The first thing to be clear about is that Memory Ballooning is a technique that is only engaged when the host is running low on physical memory. If you have a host with 60 GB of physical memory available and the virtual machines are only allocated a total of 30GB of memory, then you may never need to know what memory ballooning is all about. However if you are over committing your hosts then this is an important topic to review. ...

One of the companies I worked for got a Netapp filer and I loved the fact that it would dedupe the data that was sitting on disk. I got over 40% more storage just by having that sweet little feature on. I was thinking, “How awesome would it be to dedupe my memory?” Getting more memory out of my servers would be a nice thing. Well as it turns out, VMware does this already, but they call it “Transparent Page Sharing.” ...

Jumbo frames can be useful to optimize IP networks, especially in storage networking. This post should help to explain why using jumbo frames can be useful. I’m not Jumbo, I’m just big boned! First, let’s define what we mean by the term jumbo frame. As you can imagine it’s bigger than a normal frame. A Jumbo frame simply means any frame with an MTU larger than 1500 bytes. What exactly does that mean? To really understand that we need to look at an Ethernet frame. The diagram below shows a hastily thrown together Ethernet frame and most of the frame we’re not concerned with for this topic. Parts of the frame are used for determining where the frame is headed, where it came from and to make sure it arrived intact. The section we’re looking at is the “Data” or “Payload” section of the frame. ...

HP Enterprise class storage has just entered the mid range market. Today HP announced the HP 3PAR StoreServ 7000 class which includes two devices; the HP 3PAR 7200 and the HP 3PAR 7400. The 7200 starts at $25k for the 2U device and the 7400 (seen below) is less than $40K for a 4U device. I’m very excited about this announcement because now HP has a storage device with the features that everybody wants and it’s now affordable for a smaller sized organization. HP has seemingly targeted one of it’s own devices with this announcement (the HP EVA) since it has been very popular with the mid-range business. They’ve even included some tools to migrate data from the EVA to the new 3PAR. I seriously doubt that the EVA will entirely go away, but the new big brother is going to steal some of their thunder. ...

When you team NICs together in ESXi 5 you can pick from a variety of load balancing techniques to determine how traffic should flow over the adapters. You might think that setting up software iSCSI initiators in ESXi would be done in a similar manner. Add a VMkernel to a vSwitch, add a couple of adapters and set a teamingfailover policy. It turns out that this is not the case. You could setup a software iSCSI initiator this way, but it won’t provide you the teaming or failover you’ve intended. ...

I just found out that I’ve passed the VMware Certified Advanced Professional 5 - Datacenter Administration exam and wanted to share my experience. When I first set out to take on this exam, I was apprehensive about it because of the number of possible questions that could be asked on it. The blueprint was quite large and covered basically everything related to vSphere. I got some helpful advice from a friend who told me that instead of worrying about if I could pass the exam, think about it like vSphere Olympics. It’s a chance to show off how much you know. It was a subtle change, but a different mindset really helped me. ...

Over the past few weeks, I’ve been hearing a lot of customers having issues logging into vCenter after upgrading to vSphere 5.1. I upgraded the lab and had some issues as well, but was able to fix the issues and wanted to share what I’ve learned. As you may know version 5.1 of vSphere requires the SSO service to be installed before vCenter can be upgraded. SSO is required for this version and cannot be skipped. ...

I recently tried out the HP Insight Control plugin for vCenter and was very pleased about the added functionality that was provided in my vSphere client. http://h18013.www1.hp.com/products/servers/management/integration.html This plugin gives you additional control of your HP servers and storage that are being used by your vSphere environment. Like other storage vendors, the install will configure your VASA plugin, and will also allow you to do things such as create datastores and snapshots on the storage array from the vSphere Client. ...

 I’ve written posts in the past regarding LUN masking on a storage array, but it is possible to mask a path directly from your vSphere environment. I feel that if at all possible the masking should be handled at array level because the array is closest to the disk. Let’s face it, if vSphere shouldn’t see a LUN for one reason or another, then why is the array presenting it in the first place? ...

As you may well know, when installing VMware ESXi on an HP server, it is best practice to get a specific image of the hypervisor with the vendor’s drivers included. This will prevent issues such as having missing network cards once you’ve installed ESXi. But what about keeping the server up to date? Many companies update their servers on a monthly basis for compliance reasons or just best practices. It has been my experience that VMware patches are usually deployed at the same time. VMware Update Manager (VUM) can push updates to the ESXi hosts with the latest patches from VMware, but did you know that you can also use it to patch HP Drivers and CIM providers? ...