WilliamLam.com

Customizing the ESXi DCUI to show number of VMs

by // 7 Comments

Last week there was a question that was posted internally asking if it was possible to customize the ESXi DCUI screen to include the number of Virtual Machines? Although there is nothing out of the box, you can in fact add add almost anything to the DCUI screen by modifying the /etc/vmware/welcome configuration file which I had blogged about several years back on adding a splash of color to the ESXi DCUI. There was even a recent VMware Fling that provides a VIB that applies a variety of DoD STIG implementations, one of which was to update the DCUI screen with some specific text.

However, instead of having to manually edit the file directly on the ESXi host, we also provide an API in the way of an ESXi Advanced Setting called Annotations.WelcomeMessage which can then be updated remotely using anyone of the vSphere SDK/CLIs that you are familiar with.

Here is an example PowerCLI snippet to connect to an ESXi host (you can also do this by connecting to vCenter Server) and extracting all Virtual Machines residing on the host and then updating the DCUI screen with the total number of VMs as well as the names of each VM. Obviously, if you have more than 10 or so VMs, it may not make much sense to actually list them as it will just run off the screen, but this just gives you an example of some of the things you can do leveraging the vSphere API or any other data that you might have at your disposal.

[Read more...]

vCenter Server 6.0 Tidbits Part 6: Customizing VCSA's DCUI

by // Leave a Comment

For those of you who have deployed the latest VCSA 6.0, you may have noticed that it now includes a DCUI interface similar to that of ESXi. Just like ESXi, it provides some basic functionality such as network configuration, restarting of the management interface, enabling SSH/Shell access and viewing support logs. For some customers, there is a mandatory requirement in terms of compliance to be able to display a security or warning banner prior to logging into a system which can also include interactive console UI's like the DCUI.

With ESXi, it was possible to customize the DCUI as seen in the screenshot below (more serious customizations are used in customer environments of course). For more details, please take a look at this blog post here.

[Read more...]

How to restart the ESXi management network via command-line?

by // 11 Comments

A great question that was brought up on Twitter yesterday by Andreas Peetz who asked the following:

Is there a way to restart the mgmt network in ESXi via a cmd line? You can do this from the DCUI, but I want a script! 

There are a variety of reasons why you would want to restart the Management Network on your ESXi host and usually it is related to troubleshooting or configurations such as renewing the DHCP lease on a particular VMkernel interface. For Andreas, it was renewing the DHCP lease and this is actually a use case I have heard from others before. Currently, the only way to restart the Management Network for your ESXi host is using the DCUI (Direct Console User Interface) either through the console using iLO/iDRAC/etc. or remotely over SSH.

Andreas' question is not a new one and I have heard this ask in the past. I have even inquired about it when I was a customer but was told it was not possible and had to use the DCUI. I was not really satisfied with the answer I provided to Andreas, so I decided to do a bit of digging myself and ping some engineers. Apparently this functionality is actually exposed through a legacy command-line utility called esxcfg-vmknic in the ESXi Shell as well as locally/remotely via the ESXCLI network namespace which is used to manage the VMkernel interface (Thanks to Andres for mentioning ESXCLI method).

There are two flags that this command supports which is to enable and disable a VMkernel interface. This is actually what the DCUI is doing when you ask it to restart the Management Network and is very similar to restarting a service on a UNIX/Linux system, it first shutdowns the service and then starts it back up. Given this information, if you wish to restart the Management Network of your ESXi host you can specify the name of the Management Network portgroup and execute the enable operation immediately after performing the disable operation.

To do this from the command-line, you would add a ; (semi-colon) between the two commands so they are executed one after another to ensure your VMkernel interface is enabled after you have disabled it. Here is an example of the command:

esxcli network ip interface set -e false -i vmk0; esxcli network ip interface set -e true -i vmk0