VSAN 6.0 Part 9 – Proactive Re-balance

This is another nice new feature of Virtual SAN 6.0. It basically is a directive to VSAN to start re-balancing components belonging to virtual machine objects around all the hosts and all the disks in the cluster. Why might you want to do this? Well, it’s very simple. As VMs are deployed on the VSAN datastore, there are algorithms in place to place those components across the cluster in a balanced fashion. But what if a hosts was placed into maintenance mode, and you requested that the data on the host be evacuated prior to entering maintenance mode, and now…

Tips for a successful Virtual SAN (VSAN) Proof Of Concept (POC)

Pretty soon I’ll be heading out on the road to talk at various VMUGs about our first 6 months with VSAN, VMware’s Virtual SAN product. Regular readers will need no introduction to VSAN, and as was mentioned at VMworld this year, we’re gearing up for our next major release. With that in mind, I thought it might be useful to go back over the last 6 months, with a look at some successes, some design decisions you might have to make, what are the available troubleshooting tools, some common gotchas (all those things that will help you have a successful…

vsan.resync_dashboard only reports VM resyncing, not templates

While doing some testing yesterday in our lab, we noticed that after we had placed a host participating in a VSAN cluster into maintenance mode and chose the option to evacuate the data from the host to the remaining nodes in the cluster, the “Enter Maintenance Mode” task was still sitting at 63% complete even though it seemed that the resynchronization of components was complete. For example, when we used the vsan.resync_dashboard RVC command, there were 0 bytes left to sync: > vsan.resync_dashboard /localhost/ie-datacenter-01/computers/ie-vsan-01/ 2014-11-06 12:07:45 +0000: Querying all VMs on VSAN … 2014-11-06 12:07:45 +0000: Querying all objects ..…

Heads Up! Incorrect reporting of Outstanding IO in VSAN Observer

Hi all, A quick note to let you know about a new KB article that has recently been published which reports incorrect values for Outstanding IO in the VSAN Observer tool used for monitoring performance of VSAN deployments when using vSphere 5.5U2. KB 2091979 reports the issue as follows: Virtual SAN (VSAN) Observer graphs in the “VSAN Client”, “VSAN Disk”, “DOM Owner” or individual VSAN object on the “VM” tab show very high Outstanding I/O (OIO) value that is inconsistent with the actual I/O load. Here is a sample screenshot from my VSAN environment running vSphere 5.5U2. As you can see…

VSAN Troubleshooting Case Study

I have been doing a bunch of stuff around disaster recovery (DR) recently, and my storage of choice at both the production site and the recovery site has been VSAN, VMware Virtual SAN. I have already done a number of tests already with products like vCenter Server, vCenter Operations Manager and NSX, our network virtualization product. Next up was VCO, our vCenter Orchestrator product. I set up vSphere Replication for my vCO servers (I deployed them in a HA configuration) and their associated SQL DB VM on Friday, but when I got in Monday morning, I could not log onto…

VSAN Part 28 – RVC login difficulties

It’s interesting how a number of conversations tend to pop up around the same issue in a short space of time. I read a very interesting thread from one of our support guys recently about trying to select the correct administrator credentials for the Ruby vSphere Console (RVC). RVC is a command line utility to manage various aspects of vSphere and has been extended to include VSAN functionality. The following day, I saw a thread on the VSAN forums for exactly the same thing – a customer experiencing difficultly logging into RVC on a remote vCenter server as administrator. The…