The amount of retries is configurable as of vCenter 2.5 U4 with the advanced option “das.maxvmrestartcount”. My colleague Hugo Strydom wrote about this a while ago and after a short discussion with one of our developers I realised Hugo’s article was not 100% correct. The default value is 5. Pre vCenter 2.5 U4 HA would keep retrying forever which could [...]

This would be a good way to spent your time: Title: VIX APIs – Managing and Automating Guest OS We will show examples of how the VIX API can be used to develop tools for managing guest environments in VMware products. Included will be a demonstration of proof-of-concept tools that monitor processes and transfer files to multiple guests simultaneously. We [...]

I was “fortunate” enough to be part of the group of people who were invited to do the VCAP-DCA exam. Some of the others like Jason Boche and William Lam who recently did this exam already shared their experience. The VCAP-DCA Exam is the follow up to the VI-3 Enterprise Exam which I passed two years ago as part of [...]

Today I received a question around the difference between IOPS and CMDS/s. The reason for this was the high value of CMDS/s in “esxtop” which exceeded the expected amount of IOPS the disks could actually digest. I thought it would useful for everyone to know what the difference is: IOPS = Input/Output Operations Per Second Within esxtop this would be [...]

I never noticed this set of scripts to be honest but Anne Holler(VMware Employee) posted these about a year ago. What the scripts do is change various DRS/DPM settings to pro-actively manage your environment and change DRS and DPM behaviour based on expected workload. Proactive DRS: setDRSAggressive.pl The script setDRSAggressive.pl sets various DRS operating parameters so that it will recommend rebalancing [...]

On the community forums a question was asked around Campus Clusters and pinning VMs to a specific set of hosts. In vSphere 4.0 that’s currently not possible unfortunately and it definitely is a feature that many customers would want to use. Banjot Chanana revealed during VMworld that it was an upcoming feature but did not go into much details. However [...]

A colleague had a question around the maximum amount of host failures HA could take. The availability guide states the following: The maximum Configured Failover Capacity that you can set is four. Each cluster has up to five primary hosts and if all fail simultaneously, failover of all hosts might not be successful. However, when you select the “Percentage” admission control [...]