8.3 VCAP-DCA Study Guide – vMA (vSphere Management Assistant)
Posted on 04.Jul 2011 by Ray Heffer in Tech Tips, VCAP-DCA, Virtualisation, VMware
If you haven’t already used the vMA (vSphere Management Assistant) then I strongly encourage you to do so as it’s an essential tool in managing your ESX and ESXi hosts, and it really makes the transition from ESX to ESXi straight forward. Understanding and using the vMA is part of section 8.3 in the VCAP-DCA blueprint.
Customising the default profile in Windows 7
Posted on 13.May 2011 by Ray Heffer in Tech Tips, Virtualisation, VMware, VMware ViewConfiguring the default user profile in Windows 7
When creating your base (parent) image you may want to configure the default user profile so when new users log into the desktop for the first time, it retains certain customisations such as the desktop background colour, shortcuts, etc. Prior to Windows 7 you were able to copy a user profile to the default user profile, but Windows 7 does not permit this method. Instead, you must create an unattend.xml (unattended installation file) with Windows System Image Manager (WSIM) which is part of the Windows Automated Installation Kit.
VMware ESXi 4.1 Kickstart Scripted Deployment with UDA (PXE BOOT)
Posted on 18.Mar 2011 by Ray Heffer in ESX, ESXi, Linux, Scripts & Commands, Tech Tips, Virtualisation, VMwareIf you are looking to deploy multiple ESX/ESXi servers then there are plenty of methods and tools out there, some more complex than others. There are vendor specific deployment products available such as HP Rapid Depuployment Pack (RDP) which uses Altiris, or alternatively there are free deployment tools such as ESX Deployment Appliance (EsleeDA) and Ultimate Deployment Appliance (UDA). UDA is my favorite tool for the job as it offers great flexibility such as the use of subtemplates (discussed later), and therefore this will be the basis of this article. It was created by Carl Thijssen and thanks to Mike Laverick of RTFM, it also supports ESX/ESXi deployments, and the latest build supports ESX/ESXi 4.1.
Changing text typing repeat delay on a VMware virtual machine
Posted on 17.Mar 2011 by Ray Heffer in ESX, ESXi, Tech Tips, Virtualisation, VMwareIf you find that when typing text using the VMware virtual machine console on a low bandwidth connection, it repeats characters (no matter how careful you are). Try setting the following configuration parameter:
keyboard.typematicMinDelay = 2000000
You’ll need to power off your VM first, then add this to the end of your configuration (.vmx) file. If you are using VMware ESX/ESXi then edit the settings of the virtual machine and go to Options then Advanced, General > Configuration Parameters.
VMware KB 196: http://kb.vmware.com/kb/196
8.3 VCAP-DCA Study Guide – Introduction to vMA (vSphere Management Assistant)
Posted on 24.Feb 2011 by Ray Heffer in ESX, ESXi, Tech Tips, VCAP-DCA, VMware
The vSphere Management Assistant (vMA) runs a 64 bit operating system (RedHat Enterprise Linux) and features the VMware vCLI in addition to vSphere SDK for Perl, Java JRE, CIM vSphere profiles, VMware tools and an SNMP agent. The vMA virtual machine requires a single vCPU with 512MB memory and a 5GB virtual disk. If you are studying for the VCAP-DCA exam then you will need to know how to install and use the vMA to manage a vSphere environment. The best way to learn how to use the vMA is to setup your own home lab. I’ve already posted an article on building a whitebox VMware vSphere server for your home lab (click here), otherwise you can always use VMware Workstation on your PC or laptop.
8.3 VCAP-DCA Study Guide – Changing the vMA IP address
Posted on 09.Feb 2011 by Ray Heffer in Tech Tips, VCAP-DCA, Virtualisation, VMware Here is a very quick and dirty tech tip on changing the IP address of your VMware vMA. There are two ways of doing this, the Linux way or the VMware Setup Wizard.
VMware vSphere 4.1 – HA Admission Control Slot Calculation
Posted on 07.Feb 2011 by Ray Heffer in ESXi, Tech Tips, Virtualisation, VMware
VMware HA (High Availability) admission control is something I wanted to understand better so I started making notes gathered from various sources on the subject, and in particular the way slot sizes are calculated. Duncan Epping’s Yellow Bricks site already covers HA very well and I bow down to his knowledge on the subject, well worth checking out. Also I would strongly recommend VMware vSphere 4.1 HA and DRS Technical Deepdive by Duncan Epping and Frank Denneman which I purchased at Comcol.nl which they shipped to me in the UK in just two days.
That said, I thought I would share my own views and notes I have taken on the subject. The vSphere Availability guide states “A slot is a logical representation of memory and CPU resources. By default, it is sized to satisfy the requirements for any powered-on virtual machine in the cluster.” – In simple terms a slot can be consumed by a single virtual machine, but a virtual machine may consume more than one slot.
Use Cases for VMware ESX 3.x DisallowSnapshotLUN and ESX 4.x Force-Mount
Posted on 21.Jan 2011 by Ray Heffer in ESXi, SAN Storage, Tech Tips, Virtualisation, VMware
If you are involved in DR for your organisations IT infrastructure and are replicating virtual machine VMFS datastores then you may be familiar with DisallowSnapshotLUN in ESX 3.x. Let’s start with a background on what these advanced settings are and why they are there.
Since virtualization changed the landscape for disaster recovery some time ago now, most businesses have embraced SAN storage replication for DR (see my other post). This is old news now, but unless your SAN vendor integrates with something like VMware Site Recovery Manager (SRM) then you will have a number of manual tasks involved in your DR recovery process.
Building a Remote Desktop Gateway (RDG) / RD Gateway Server
Posted on 05.Jan 2011 by Ray Heffer in Business & IT, Microsoft, Tech Tips, Windows Server 2008 R2Creating a Remote Desktop Gateway (RD Gateway) is straight forward and can be used to securely access your Windows servers over port 443 using the Remote Desktop Connection Client. I use this to access my home lab when I’m on the road or at work, and it saves exposing your machines to the internet directly over RDP (TCP 3389). The RD Gateway isn’t new, in fact it was available on Windows Server 2008 as TS Gateway, and the installation is the same. For this article, I will be using Windows Server 2008 R2.
VMware vSphere ‘Whitebox’ Server Lab Setup – Part 3
Posted on 04.Jan 2011 by Ray Heffer in ESXi, Home Lab, Tech Tips, Virtualisation, VMwareThe third part of this series continues with the vSphere build on my whitebox server, the Asus Rampage II Extreme with Intel Core i7 2.8Ghz and a 120GB SSD. Following on from the video in part 2 where we installed ESXi on to the USB drive, we are now ready to access the physical ESXi host and start creating some virtual machines. Since this is a home vSphere lab environment, accessing the lab from anywhere (not just at home) is a major advantage for me, so I’ll be taking you through the steps to create a Microsoft Windows Server 2008 R2 virtual machine with an RD Gateway (Remote Desktop Gateway). We will also need shared storage in order to use vMotion, so I will also guide you through the setup of an OpenFiler iSCSI virtual SAN.
VIDEO: VMware vSphere ‘Whitebox’ Server Lab Setup – Part 2
Posted on 10.Dec 2010 by Ray Heffer in Home Lab, Tech Tips, Virtualisation, VMwareFollowing on from part 1 of my VMware vSphere ‘whitebox’ sever series, this video provides an overview of the build, and installation and configuration of ESXi.
VMware vSphere ‘Whitebox’ Server Lab Setup – Part 1
Posted on 07.Dec 2010 by Ray Heffer in Business & IT, Home Lab, Tech Tips, Virtualisation, VMwareIntroduction
Way back when VMware VI3 was released in 2006 (doesn’t time fly!), I built a home-brew lab server for ESX 3.0 and used it partly to study for my VCP exam. That particular machine is now my home theatre PC (HTPC) as it wouldn’t stand a chance of running VMware vSphere, so here is my mission to build a whitebox VMware vSphere lab server. I must also give credit to Simon Seagrave and Simon Gallagher their vSphere lab server articles which have inspired me to do something about it and build a vSphere lab at home. Simon has lots of great articles on building a vSphere lab, and I urge you to visit his site.
Virgin Media 50Mb broadband only achieving 35-40Mb with certain routers
Posted on 05.Nov 2010 by Ray Heffer in Tech Tips
If you have upgraded to the Virgin Media 50Mb broadband and use a Linksys router then you may not get optimum speeds, typically around 37Mb. However, with the Tomato custom firmware you’ll be able to get the full 50Mb from your router. It also features some great bandwidth monitoring and other advanced features, well worth a look.
http://www.polarcloud.com/tomato
How to make a CAT5 crossover cable
Posted on 28.Jan 2010 by Ray Heffer in Tech TipsIf you are in need of a CAT5 crossover cable, but can’t find one then it’s very easy to make one providing you have the right tools.
This is what you need:
Length of CAT5 (or CAT5e / 6) cable
Wire cutters
RJ45 connectors
RJ45 crimper
Linux commands and tips
Posted on 07.Jul 2005 by Ray Heffer in Linux, Scripts & Commands, Tech Tips
Checking kernel & CentOS version
To check which kernel version you are running use uname -r
# uname -r
To find out which CentOS (or RedHat) release is installed have a look at /etc/redhat-release
# cat /etc/redhat-release
Checking Disk Space
To check disk space used / free use the df command and it will display each volume. The -h switch turns the bytes reading into GB to make it more readable.
# df -h
If you want to check the size of a particular directory then use:
# du -sh /
