Virtual MAC address assignments are based on Microsoft’s organizationally unique identifier (OUI) registration with the Institute for Electrical and Electronic Engineers (IEEE). An OUI is a unique MAC address prefix assigned that is assigned to all NIC vendors, both physical and virtual.
VMware Organizationally Unique Identifier (OUI) allocation uses the default OUI 00:50:56 as the first three bytes of the MAC address generated for each virtual network. The MAC address-generation algorithm produces the rest of the MAC address. The algorithm guarantees unique MAC addresses within a virtual machine and attempts to provide unique MAC addresses across virtual machines.
The VMware Universally Unique Identifier (UUID) generates MAC addresses that are checked for conflicts. The generated MAC addresses are created by using three parts: the VMware OUI, the SMBIOS UUID for the physical ESXi machine, and a hash based on the name of the entity that the MAC address is being generated for.… Read More
svMotion is fair simple process and nothing much complex is involved in that. Here are the step by step breakdown of what happens in background of svMotion process:
The virtual machine working directory is copied by VPXA to the destination datastore.
A “shadow” virtual machine is started on the destination datastore using the copied files. The “shadow” virtual machine idles, waiting for the copying of the virtual machine disk file(s) to complete.
Storage vMotion enables the Storage vMotion Mirror driver to mirror writes of already copied blocks to the destination.
In a single pass, a copy of the virtual machine disk file(s) is completed to the target datastore while mirroring I/O.
Storage vMotion invokes a Fast Suspend and Resume of the virtual machine (similar to vMotion) to transfer the running virtual machine over to the idling shadow virtual machine.
After the Fast Suspend and Resume completes, the old home directory and virtual machine disk files are deleted from the source datastore.
Prior to vSphere 5.0 it was not possible to storage vMotion a VM that is running with snapshots. With 5.0 VMware has enhanced svMotion and included this feature as lot of customers were demanding for that.
But there is one caveat in this feature which many of us don’t know due to lack of documentation on this. I found one very useful article on VMware Blog and thought of sharing with you.
workingDir parameter
The location of a virtual machine’s snapshot redo log file is defined by the virtual machine .vmx file setting workingDir. By default, the workingDir property is the same as the virtual machine’s home directory. What this means is your snapshot is stored in the same directory where your VM base disks are residing.
if you don’t have enough space on datastore where your VM disk is currently placed and you want to take snapshot on that VM, then by use of workingDir parameter you can store snapshot to another location/datastore.… Read More
Esxcli network vswitch command is used to do the networking configuration of a vswitch (Standard or vDS). The available namespace with this command are: standard and dvs as shown below
To list all Standard vSwitch present on the Esxi host
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# esxcli network vswitch standard list
Add Remove vSphere Standard Switch
We can add/remove new standard switches or create a new portgroup in vswitch or associate uplinks to vswitch using the command
# esxcli network vswitch standard
The namespaces associated with the above command as shown below
Adding a new vSwitch to Esxi host
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# esxcli network vswitch standard add –v=Name of vSwitch
Example:
# esxcli network vswitch standard add –v=vSwitch5
Adding a new vswitch with specific number of ports
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# esxcli network vswitch standard add –v=vSwitch5 - -ports=256
Note: By default when a vSwitch is created it is created with 128 ports
Configuring Port Group on Standard Switches
Port groups are configured on vSwitch using the command
# esxcli network vswitch standard portgroup
The associated namespace with this command are as shown below:
Create a new portgroup in a standard vswitch
The following command is used to create a new portgroup on a standard vSwitch
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# esxcli network vswitch standard portgroup add –p= name of port group –v= Name of vSwitch
Example:
# esxcli network vswitch standard portgroup add –p=”FT NW” –v=vSwitch6
Removing a portgroup from a vSwitch
Below command will delete a portgroup from a standard vswitch
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# esxcli network vswitch standard portgroup remove –p=”FT NW” –v=vSwitch1
Configuring CDP on Standard switches
Configuring CDP settings or MTU on a standard vswitch is done using the command :
# esxcli network vswitch standard set
To enable CDP on a vswitch
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# esxcli network vswitch standard set –c= cdp mode –v=vSwitch name
The accepted values forCDP islisten,advertise andboth
Example:
# esxcli network vswitch standard set –c=listen –v=vSwitch5
To disable CDP on a vswitch
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<span style="color: #000000;"><em># esxcli network vswitch standard set –c=down –v=vSwitch5</em></span>
Configuring uplinks for Standard vSwitch
The command used to add/remove uplinks to a standard vSwitch is
# esxcli network vswitch standard uplink
Adding an uplink to an existing vSwitch
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<span style="color: #000000;"><em># esxcli network vswitch standard uplink add –u=uplink name –v=vswitch name</em></span>
Last week I was facing a serious issue in my home lab where my esxi host is getting disconnected from my vCenter Server randomly. Whenever I am doing any configuration changes like enabling ssh or creating a new vSwitch the host got disconnected immediately. I was damn frustrated and was looking for a solution because it was very hard for me to work.
So I started troubleshooting by going through my vCenter log files and found following:
With vSphere 6.0 Vmware has enhanced so many features and host profile is one of them. Let’s refresh what host profile do. A plain simple definition of host profile is:
“Host Profiles allow you to configure standard configurations for your ESXi hosts and to automate compliance to these configurations, simplifying operational management of large-scale environments and reducing errors caused by misconfigurations”
Two main features that are enhanced in vSphere v6.0 are:
Maintenance Mode Removal
Till release of vSphere 5.5 host profile required hosts to be put in maintenance mode before you can apply the profile. This can be a very inconvenient task when you are trying to change some configuration during normal business hours specially when the Host:VM consolidation ratio is high.
With vSphere 6.0 Vmware has made host profiles a bit intelligent. Now a host profile will require a host to be put into maintenance mode only if the configuration settings defined in host profile requires it.… Read More
Today I was reading one of the Duncan Epping’s blog and found one useful info related to HA so thought of sharing with you all.
We all are aware of DRS affinity and anti-affinity rules and we know the fact that HA doesn’t respect the VM-Host should rules and if any host fails then HA can restart the VM’s anywhere and not necessarily on the host to which VM’s has affinity rules tied up.
However on next invocation of DRS (default 5 minutes) this violation would be corrected by DRS itself and VM’s will return to the host according to the VM-Host affinity rules.
With vSphere 6.0 VMware has introduced one new advanced configurable option in HA. This setting is called “das.respectVmHostSoftAffinityRules”.
As the name itself suggests, this setting will let HA to respect VM-Host affinity rules when it can and can violate it when HA doesn’t have much choice.… Read More
Today I was looking for some tricks to tweak vCenter server 5.5 for my home lab as I have only 8 GB RAM available and my lab was damn slow. Below is my lab configuration
vCenter Server v5.5 (with embedded MS SQL Server) – Installed on Server 2008 R2 SP1 OS (Physical)
After powering on all the VM’s which are running inside vmware workstation (installed on my server 2008) my LAB has become too slow and memory utilization was shooting upto 7.8 GB.
It was nearly impossible to work anything from GUI (VI Client + Web Client) as my Esxi hosts were getting disconnected from VC time and again whenever I was doing any configuration (addition or modification) due to the SQL timeout and I was relying on just command line.… Read More
One of the new feature of vSphere 6 is Content Library . The Content Library provides simple and effective management for VM templates, vApps, ISO images and scripts for vSphere Administrators collectively called “content”.
Sometimes we have ISO and other files (needed for VM creation etc) are spread across datastores as multiple administrators are managing vSphere Infrastructure.This can lead to duplication of the contents. To mitigate this issue concept of content library is introduced in vSphere 6.o which allows for a centralized place for storing your contents.
Advantage of Content Library
The Content Library can be synchronized across sites and vCenter Servers. Sharing consistent templates and files across multiple vCenter Servers in same or different locations brings out consistency, compliance, efficiency and automation in deploying workloads at scale.
Following are some of the features of the content library:
Store and manage content – Once central location to manage all content as VM templates, vApps, ISO’s, scripts etc.
Every year vExperts are chosen all round the world for their contribution towards the VMware community and for their efforts VMware offers the vExperts access to community (private forum, access to beta products etc.)
Besides the public recognition of being a vExpert, they get additional benefits like free subscriptions, NFR licenses and so on from 3rd party vendors. However the information given below is available on the vExpert Community Page but still I am sharing this so that if anyone has missed it, they can checkout the benefits for year 2015 from here.
