What a great question!  What are nine things that can cause you to run out of capacity resources in your VMware ESX Server data center environment and run into performance problems or even cause downtime? 

The question and answers come from Alex Bakman, Founder and CEO of V-Kernel.  Alex offers the following nine items as an answer to this question on his blog:

1. Adding new VMs though uncontrolled VM sprawl
2. Removing hosts from clusters
3. HA enabling your cluster without accounting for fail over
4. Changing Fail Over Capacity setting in a Cluster
5. Increasing reservations in VMs
6. Changing Resource Pool Configurations
7. Power up many VMs that were powered off or in maintenance
8. Natural growth rates in Storage, CPU, Memory and Network utilization
9. Changes in workloads can result in Disk I/O bottlenecks

Got a comment?  How about others?  Send them over to Alex, here.