What is SR-IOV (Single Root I/O Virtualization) ?

SR-IOV is a technology, by Intel created to improve the networking performance of virtual machines. Interrupts First of all it is important to explain how interrupts are involved within packet processing. The process to remove and read packets from the wire, in both virtualized and non-virtualized systems is interrupt driven. When a packet is received … Read more

VMware VLAN Tagging Methods – EST, VST and VGT

Within VMware there are 3 methods around VLAN tagging. They are EST, VST and VGT. Below shows the differences between the 3, Type Physical (VNIC) Virtual (vSwitch) EST Access port Access port VST Trunk port Access port VGT Trunk port Trunk port EST Within EST (External Switching Tagging) VLAN tags are not handled[1]. The physical switchport … Read more

VMware vCentre/vSphere ‘Unknown VM’ and Inaccessible

Issue Within the vSphere client or vCentre your virtual machine(s) are named as ‘Unknown VM’ and are inaccessible. Solution This can be caused by connectivity issues between the hypervisor and its datastore. To resolve the issue follow these steps, Log into the virtual machines host via SSH. Then change directory via the command  ‘cd /var/lib/vmware/hostd/stats‘. … Read more

How to run vSphere using SSH tunnelling

This guide looks at running your vSphere Client through SSH tunnels. You may need to do this due to having a Proxy in place or your firewall is blocking the required ports you need in order to run vSphere. 1. First of all edit your hosts file to include an entry for you ESX box. … Read more

ESX4: Turn on/off Virtual Machine using Command Line

Using the vmware-cmd command you can perform a number of actions on your Virtual Machines from the command line. Below shows you some of the functions you can perform : List Virtual Machines [root@ESX4 ~]# vmware-cmd -l /vmfs/volumes/4c16a0ec-2c7ebe2a-6ad5-0011s8azz71c/OpenSolaris 2009.06/OpenSolaris 2009.06.vmx /vmfs/volumes/4c16a0ec-2c7ebe2a-6ad5-0011s8azz71c/CentOS 5 – Oracle/CentOS 5 – Oracle.vmx /vmfs/volumes/4c16a0ec-2c7ebe2a-6ad5-0011s8azz71c/CentOS 5a/CentOS 5a.vmx Turn On Virtual Machine Below … Read more

Adaptec Storage Manager Script for ESX4

This article shows you how to script and alert (via email) for when any of your RAID disks show as offline or your Logical Drive is not showing as optimal. In order to obtain all the stats about your Adaptec RAID card from your ESX box you can install the asm (adaptec storage manager) rpm … Read more

When running tcpdump in ESX I only see broadcast traffic

When running a tcpdump within ESX you may see only broadcast traffic this is due to your vSwitch not being in promiscuous mode. To resolve this do the following : Within the vShpere Client go to Configuration / Networking. Choose the virtual switch that your would like to capture the traffic on. On the virtual … Read more

How do I run a packet capture on ESX ?

In order to run a tcpdump on ESX you will need to add a service console to your virtual switch. This is achieved via the following steps : Set the Virtual Switch to Promiscuous Within the vShpere Client go to Configuration | Networking. Choose the virtual switch that your would like to capture the traffic … Read more

ESX Error: The specified key, name or identifier already exists

To resolve the issue of the error :      The specified key, name or identifier already exists From the command line of the ESX box run the following command : [root@ESX root]# service mgmt-vmware restart If this fails to resolve the issue run the following commands : service mgmt-vmware restart service vmware-vpxa restart service vmware-vmkauthd … Read more

How do I create a trunk port in ESX ?

In order to create a trunk port in ESX you need to : Within vSphere or ViClient go to the “Configuration” tab. Select “Networking“ Select your “Add Networking“. Choose “Virtual Machine” and click “Next“ Select your Virtual Switch (or create one), then click “Next“ Choose you Network label and then add the VLAN ID as … Read more

vSphere/VI Client: User name or password has an invalid format

Issue When trying to add a user you get the following error message, User name or password has an invalid format Solution This can be down to either Your password is not eight characters in length. Your password or username entered contained characters outside of the character types allowed. These are : – Alphanumeric Characters … Read more

vSphere – Creating User and Group Permissions

This tutorial was created using the vSphere client, but the general steps should pretty much the same for the Virtual Infrastructure Client.If you are using vCentre please read the notes relating to this at the bottom of the article. Create Privileges Click “View | Administration | Roles” Right client and cick “Add” Select a name … Read more

ESXi – Connecting to a named pipe

Within this article we will be creating a named serial pipe on 2 machines to allow us to connect to a virtual machines serial port. In this example we will use hyperterminal on a virtual XP machine to connect to the serial port of another virtual machine (in this case SUSE Linux) Adding a serial … Read more

ESX Convertor (Windows 7) – The session is not authenticated

When trying to authenticate, and convert machines within your VMware convertor you recieve the following error :      The session is not authenticated Fix Close VMware Convertor Goto ‘Start / Run’ and type services.msc. Restart the services VMware vCenter Converter Agent and VMware vCenter Converter Server Relaunch VMware Convertor. Still have Issues ? If this … Read more

ESX Convertor – The session is not authenticated

Issue When trying to authenticate, and convert machines within your VMware convertor you recieve the following error :        The session is not authenticated Fix Within windows go into your task manger and kill all of your VMware convertor processes that are currently running. Reference http://communities.vmware.com/thread/195575 Still have Issues ? If this has still not … Read more

ESX – ViClient Cannot connect to host

Issue When trying to connect to the console within the VI Client you receive the following error,               Cannot connect to host my.esx.host.com: no connection could be made because the target machine actively refused it In this example you have the required ports open on both your firewall and your ESX box. You see … Read more

Solaris / ESX – Networking Issues

Networking connectivity Issue / Dropping packets Ok, so I finally installed Solaris 10 32bit, but then found that the network interface keep dropping packets (??)To fix this I installed VMware tools which installs a new vmxnet driver but as a result this also renames your interface to vmxnet0.  Installing VMware tools has affected your machine … Read more

ESXi – How to enable SSH

To enable SSH you will need to do the following, In the ESXi console press ALT+F1 Type unsupported(as you type you will not see anything on the screen) Enter the root password Edit the file /etc/inetd.conf and find the line which has #ssh and remove the #. Then Type /sbin/services.sh restart

ESXi White Box – HP DL140

White Box is a term used to describe a hardware spec/platform that has been used outside of the Vendors recommendations. In order to run VMware ESXi on a platform outside of the Vendors HCL (Hardware Compatibility List) I used various Whitebox resources to run ESXi on the below, HP Proliant DL140 G1 (2x 3Ghz Xeons … Read more

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