Cluster

My vSphere lab is split into two halves - a low power management cluster, powered by 3 Intel NUCs, and a more hefty workload cluster powered by a Dell C6100 chassis with 3 nodes. The workload servers are noisy and power hungry so they tend to be powered off when I am not using them, and since they live in my garage, I power them on and off remotely.

The recommendations for the vRealize Appliance have changed with 6.2, the published reference architecture now does not recommend using an external Postgres database (either vPostgres appliance, a 3rd party Postgres deployment or using a third vRealize Appliance as a stand-alone database installation). Instead the recommended layout is shown in the diagram below. One instance of postgres on the primary node becomes an active instance, replicating to the second node which is passive. In front of these a load balancer or DNS entry points to the active node only. Fail-over is still a manual task, but it does provide better protection than a single instance.

vRealize Log Insight 2.5 improves on the clustering in previous versions with an Integrated Load Balancer (ILB) which allows you to distribute load across your cluster of Log Insight instances without actually needing an external load balancer. The advantage of this over an external load balancer is that the source IP is maintained which allows for easier analysis.

The minimum number of nodes in a cluster is three, the first node becomes the Master node and the other two become Worker nodes. The maximum number of nodes supported is six, though acording to Mr Log Insight himself, Steve Flanders , the hard limit is more:

With the release of vCAC 6.1 there have been some great improvements in the setup of the clustered vCAC appliances - none of the previous copying of configuration files between appliances - just a simple wizard to do it all for you. In my opinion this is superb.

You’ll need to have deployed a load balancer of some sort - vCAC 6.0 build-out to distributed model – Part 3.1: Configure Load Balancing with vCNS or vCAC 6.0 build-out to distributed model – Part 3.2: Configure load balancing with NSX

This is the fourth article in a series about how to build-out a simple vCAC 6 installation to a distributed model.

By the end of this post we will have deployed a second vCAC Appliance, clustered it with the first appliance and registered the load balanced URL with the Identity Appliance. This will mean logging on to https://vcloud.definit.local/shell-ui-app will be successful.

An overview of the steps required are below:

In my previous post Backing up ESXi 5.5 host configurations with vCenter Orchestrator (vCO) – Workflow design walkthrough I showed how to create a workflow to back up host configurations, but it was limited to one host at a time. For this post I’m going to show how to create a new workflow that calls the previous one on multiple hosts using a ForEach loop to run it against each one. This was actually easier than I had anticipated (having read posts on previous versions of vCO that involved created the loops manually).

Here’s a lesson in checking the basics! I added new ESXi 5 host to a cluster today and spent a good couple of hours troubleshooting the error:

vSphere HA agent for host [Host’s Name] has an error in [Cluster’s Name] in [Datacenter’s Name]: vSphere HA agent cannot be correctly installed or configured

After a few basic checks, migrating the host in and out of the cluster and rebooting, I headed off to google and began troubleshooting.