Production incidents in virtualized environments have a different character than physical infrastructure failures. The failure radius can be much larger (one host failure impacts many VMs), the failure modes are sometimes subtle, and the time pressure to recover can lead to decisions that compound the original problem. These are some of the patterns I’ve seen, … Read more
Enterprise VMware environments have tools like vRealize Operations for capacity management. SMB environments running five to twenty ESXi hosts typically don’t — and they don’t need to. Good capacity planning is achievable with PowerCLI, a spreadsheet, and consistent measurement discipline. The Three Resources That Matter For most VMware workloads, three physical resources constrain capacity: CPU, … Read more
The best VMware environments I’ve managed didn’t stay healthy by accident — they had a consistent operational review process that caught problems before they became incidents. A weekly health check routine doesn’t need to be elaborate, but it does need to be consistent. The 15-Minute Weekly Review Every Monday morning before business hours, I run … Read more
“The VMs are slow” is the most common call I get about VMware environments, and it’s almost never useful information on its own. What I need to know — and rarely have if nobody’s been tracking it — is what “slow” means relative to baseline. Performance baselining is the practice of capturing normal behavior metrics … Read more
Storage vMotion is the capability that makes VMware environments operationally flexible — you can move a VM’s virtual disks from one datastore to another while the VM continues running, without any user-visible downtime. Understanding how it works and what can go wrong makes it a tool you can use confidently. How Storage vMotion Works Storage … Read more
ESXi 5.5 reached end of general support in September 2018, creating real urgency to move environments that had been running the same version for three to four years. The upgrade path to 6.5 (the stable target at the time) had some gotchas that weren’t clearly documented in a single place. Here’s what the actual upgrade … Read more
When I first deployed Pure Storage in a VMware environment around 2017, the experience was different from anything I’d done with traditional SAN arrays. The management interface is genuinely simple, the performance headroom is substantial, and the VMware integration through the Pure vSphere Plugin changes some fundamental operational assumptions. Here’s what to know going in. … Read more
vSphere cluster misconfigurations don’t always cause immediate problems. Sometimes they sit dormant for months before a host failure or upgrade event triggers a failure mode that the misconfiguration created. These are the ones I find most consistently when auditing SMB VMware environments. EVC Mode Not Configured Enhanced vMotion Compatibility (EVC) sets a CPU compatibility baseline … Read more
Distributed Resource Scheduler (DRS) is vSphere’s automated workload balancing engine. When configured appropriately, it silently keeps your cluster balanced without admin intervention. When misconfigured, it generates a flood of migration recommendations that overwhelm administrators or triggers constant VM movements that impact performance. Here’s how to dial it in. The Three DRS Automation Levels Manual: DRS … Read more
vSphere High Availability is one of the primary reasons to run VMware over standalone hypervisors. When configured correctly, it automatically restarts VMs on surviving hosts when a host fails — transparently, without requiring administrator action. But “configured correctly” is doing a lot of work in that sentence. What HA Actually Does (and Doesn’t) HA monitors … Read more