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Setting up a DHCP relay is a pretty common task that performed by network administrators when setting up a new LAN. If you’re not familiar with a DHCP Relay, take a look at the example below. In order for a client to get an IP Address from a DHCP Server, it sends out a broadcast once it’s plugged into the network. The broadcast is asking for any servers that are DHCP servers to reply. Remember that a broadcast is a frame that is forwarded to all hosts on a Local Area Network. The DHCP Server will reply and the client will get it’s IP Address. ...

If you’re planning on doing a full distributed installation of vRealize Automation, you’ll likely want to have some protection for the vPostgres database. Having a single point of failure defeats the purpose of doing a full distributed install. I’ve been doing a bunch of work on this lately and wanted to warn people of a gotcha if you’re using a load balancer. Non-Distributed Install To give us a better understanding, take a look at a pair of vRealize Automation Appliances that aren’t in a high availability solution. In the picture below, there are two vRealize Automation Appliances and each of them is communicating with their own embedded vPostgres Database. This is the default configuration when deployed from VMware and works just fine. ...

Clustering the vPostgres database is an important part of a fully distributed vRealize Automation install. The simple install only requires a single vRealize Appliance and an IaaS Server, but the fully distributed install requires many additional pieces including load balancers to ensure both high availability as well as handling extra load placed by users. The vPostgres database is included with the vRealize Automation appliances, but for a full distributed install, these must be modified so that there is an active and standby vPostgres database running on them. The primary vPostgres database will replicate to a standby read-only database. ...

The vSphere-land top virtualization blog voting is now over and theITHollow.com was voted #35 which is up from number forty last year. I wanted to take this opportunity to thank everyone who voted for the site. There are very few rewards for all the time that is spent posting content, but seeing that the hard work is benefiting others, and is useful to the community, are among the top for sure. ...

vRealize Automation is a great way to allow teams to deploy virtual machines and manage them throughout their entire lifecycle. You can control exactly where you want the machines deployed and the processes that must happen in order to meet company guidelines. Sometimes, you’d like to give some additional options to the end user when they deploy a machine. To do this, we can use a custom property. Build a Property in the Property Dictionary To start, lets build a new property in the property dictionary. To do this, go to the Infrastructure Tab –> Blueprints –> Property Dictionary. From there, we can add a “New Property Definition”. In the example below I’ve created a very generic “HollowTestProperty” and left the display name the same. A description is always a good idea and the Control Type I changed to “DropDownList”. This will mean that we can enter a series of values to be selected by the end user at the time of the request. Be sure to click the green check mark to save the entry. ...

VMware Tools gives you the option to synchronize the time of the guest OS with the ESXi host. Many times this isn’t necessary because the guest itself is using Network Time Protocol (NTP) or used the Active Directory domain time. Why would proper time synchronization be a problem, you might ask? Well, in a virtual environment, the CPU isn’t constantly keeping track of time like it does in a physical machine. For a more detailed explanation look at tick counting in the Timekeeping Guide. ...

If you’re in the market for a Load Balancer and don’t mind that it’s virtual, check out Kemp’s Virtual Load Balancer. Even better is if you want to try stuff out in your lab because you can get the Virtual Load Balancer for free! There are some limitations, I mean everyone has to make money some how and theres no reason to buy the cow if you get the milk for free, am I right? ...

Many of my daily activities at work now revolve around the idea of a Hybrid Cloud so some of my home lab activities have also followed suit. I realized it had been a while since I wrote up the particulars of my home lab and I’ve added some equipment so this gives me a good opportunity to show some of the upgrades. Configuration The environment consists of four physical ESXi hosts that run most of my virtual machines. These servers have three nics that handle all of the virtual machine traffic and the NFS Storage traffic to a pair of Synology NAS devices. ...

There is a new kid in town when it comes to infrastructure monitoring. Opvizor is a pretty neat little solution for identifying issues in your environment before they become a problem. The install was simple enough, only requiring me to run an installer and connect it to my vCenter Server. Once that was done, it was a matter of clicking a button to scan and upload my data back to Opvizor’s servers (anonymized data of course). These uploads are scheduled to prevent all this manual nonsense, but I couldn’t wait to see what my environment looked like so I uploaded it right away. ...

I recently made some changes to my home lab and had to create a new Cluster because of my EVC mode when I was faced with migrating my vC Ops vApp to the new cluster. I moved the hosts over, but the vApp wouldn’t go with them like the virtual machines did. vAppMigrate1 My first attempt was to export the vApp to an OVF file and reimport it to the new cluster which failed with an error. ...