Virtualization on Netdata

Best VMware Monitoring Tools: 10 Ranked Picks for 2027

Wed, 12 Aug 2026 00:00:00 +0000

Monitor Your Azure to Azure Local Migration

Wed, 08 Apr 2026 00:00:00 +0000

Netdata gives migration teams a single pane of glass across Azure cloud resources and Azure Local cluster nodes. Per-second metrics, edge-based ML, and 800+ collectors mean you can baseline source workloads, validate destination hardware, run parallel cutovers, and operate the new environment without changing tools.

Proxmox Monitoring With Real-Time Observability

Thu, 18 Dec 2025 00:00:00 +0000

Netdata delivers enterprise-grade Proxmox monitoring with per-second granularity, automated dashboards, and ML anomaly detection - all without the complexity or cost of traditional solutions.

VMware Monitoring Software Without Centralized Data

Thu, 18 Dec 2025 00:00:00 +0000

Netdata delivers per-second VMware monitoring with zero configuration, built-in ML anomaly detection, and 90% cost savings. Monitor vSphere, ESXi hosts, VMs, and hybrid clouds with true real-time visibility.

What Is A Bare Metal Server? Benefits & Use Cases

Mon, 26 May 2025 00:00:00 +0000

In a world increasingly dominated by virtualized cloud environments, the concept of a bare metal server might seem like a throwback. However, these physical powerhouses continue to play a critical role in modern IT infrastructure, offering distinct advantages for specific workloads. Understanding what is a bare metal server and why you might choose one over virtualized alternatives is key to designing efficient and high-performing systems.

What Is A Bare Metal Server? Definition & How It Works

At its core, a bare metal server is a physical computer server dedicated entirely to a single customer or tenant. Unlike virtual machines (VMs) that share the resources of a physical host through a hypervisor layer, a bare metal server gives the user direct, unmediated access to the underlying hardware – the “bare metal.” This means you have exclusive use of the server’s CPU, RAM, storage, and network interface cards.

Container vs VM - Which Is Better Option For You

Tue, 22 Apr 2025 00:00:00 +0000

Deploying applications efficiently and reliably often requires isolating them from the underlying infrastructure and from each other. Virtualization makes this possible by creating virtual representations of computing resources. Two leading technologies dominate this space: containers and virtual machines (VMs). While both offer isolation and deployment benefits, they operate fundamentally differently. Choosing between a container vs VM approach is a critical decision that impacts performance, resource usage, security, and deployment speed.

Streamlining VM Monitoring with Netdata

Thu, 01 Feb 2024 00:00:00 +0000

Simplifying Virtual Machine Monitoring

Comtegra, a leader in IT solutions for storage and virtualization, faced a significant challenge in managing a dynamic environment of virtual machines (VMs). The frequent deployment and deletion of VMs, often within a single day, created a complex scenario that was both time-consuming and difficult to monitor. This challenge was particularly pronounced for Mariusz Mieszkowski, a storage specialist at Comtegra, who noted the inefficiency of performance testing and overall infrastructure management under these conditions.

Entropy In Cryptography: Key To Security & Randomness

Wed, 03 May 2023 00:00:00 +0000

Entropy is a measure of the randomness or unpredictability of data. In the context of cryptography, entropy is used to generate random numbers or keys that are essential for secure communication and encryption. Without a good source of entropy, cryptographic protocols can become vulnerable to attacks that exploit the predictability of the generated keys.

What is Entropy?

In most operating systems, entropy is generated by collecting random events from various sources, such as hardware interrupts, mouse movements, keyboard presses, and disk activity. These events are fed into a pool of entropy, which is then used to generate random numbers when needed.

Monitor KSM performance with Netdata

Tue, 01 Nov 2022 00:00:00 +0000

Monitoring KSM (Kernel Same-page Merging) performance at deduping memory shared across VMs.

Kernel Same-page Merging (KSM)

Linux kernels store memory in pages which are moved in and out of memory as a single block. On most Linux architectures pages are 4096 bytes. KSM (Kernel Same-page Merging) is a kernel feature that scans memory looking for pages with identical content, and then de-duplicates them. The most common use-case where such duplicate pages occur is on hosts running multiple virtual machines (VMs).

Kernel Same-page Merging (KSM) Monitoring

Mon, 01 Jan 0001 00:00:00 +0000

Kernel Same-page Merging (KSM)?

KSM can greatly reduce the amount of memory used by VMs. When it finds two or more identical pages, it replaces them with a single page that is shared by all VMs that are using it.

Open vSwitch Monitoring

Mon, 01 Jan 0001 00:00:00 +0000

Open vSwitch Monitoring

What Is Open vSwitch?

Open vSwitch (OVS) is a multilayer software switch used in virtualized environments to manage network traffic. It is designed to enable network automation through programmatic extensions, while supporting standard management interfaces. OVS plays a significant role in creating highly scalable distributed networking environments.

Monitoring Open vSwitch With Netdata

Monitoring Open vSwitch with Netdata is a straightforward process which can greatly enhance your understanding of network performance and reliability. Netdata utilizes an OpenMetrics (Prometheus) exporter specifically designed for Open vSwitch, allowing users to collect and visualize key network metrics in real-time. Notably, Netdata does not require a separate Prometheus server or Grafana, simplifying the deployment process. Once data is collected, users receive automated dashboards and alerts, enabling proactive troubleshooting and network optimization.

Proxmox VE Monitoring

Mon, 01 Jan 0001 00:00:00 +0000

Proxmox VE Monitoring

What Is Proxmox VE?

Proxmox VE (Virtual Environment) is a comprehensive open-source platform for enterprise virtualization, combining powerful KVM hypervisor technology with robust container-based solutions. It allows IT teams to manage virtual machines, containers, highly available clusters, and software-defined storage, all in a single convenient solution.

Monitoring Proxmox VE With Netdata

To efficiently monitor Proxmox VE, Netdata leverages an openmetrics (prometheus) exporter. Netdata seamlessly ingests data from any Prometheus exporter. This enables IT professionals to benefit from automated dashboards, alerts, and detailed statistics, without the need for a dedicated Prometheus server or Grafana setup. With Netdata, you can visualize metrics in real-time, easily detect anomalies, and ensure your virtual environment operates optimally.

vCenter certificate expired: the STS signing cert outage nobody saw coming

Mon, 01 Jan 0001 00:00:00 +0000

vCenter is down. Not “slow” or “degraded.” Down. The vSphere Client shows a white screen or a 503. PowerCLI sessions fail to connect. API calls return authentication errors. ESXi hosts show as disconnected in bulk. Every integration that depends on vCenter (NSX, vRA, SRM, backup products) has lost connectivity simultaneously. VMs on the hosts are still running, but you cannot manage, migrate, or orchestrate anything.

You check the browser certificate on the vCenter URL. It looks fine. Months left. You check NTP. Synchronized. You check disk space. Plenty. Nothing in your standard monitoring explains why the entire management plane went dark at once.

vCenter Server Appliance Monitoring

Mon, 01 Jan 0001 00:00:00 +0000

vCenter Server Appliance Monitoring

What Is vCenter Server Appliance?

vCenter Server Appliance (vCSA) is a powerful, preconfigured Linux-based virtual machine optimized for running VMware vCenter Server and associated services. It is a vital component in managing virtualized environments, providing centralized management of virtualized hosts and virtual machines from a single console.

Monitoring vCenter Server Appliance With Netdata

Netdata offers a seamless and efficient way to monitor vCenter Server Appliance. As a comprehensive monitoring tool, it provides real-time insights and detailed metrics that are crucial for maintaining the health and performance of your vCSA environment. With Netdata’s free and open-source platform, you get simple configurations, interactive visualizations, and a low-overhead monitoring solution.

vCenter vpxd crash loop: the core service that keeps restarting

Mon, 01 Jan 0001 00:00:00 +0000

vpxd is the C++ core of vCenter Server. It holds the entire managed inventory in memory, dispatches every management task to ESXi hosts via hostd, runs DRS, executes statistics rollups, and serves every SDK client (vSphere Client, PowerCLI, Veeam, NSX Manager, Aria Operations, custom automation). When vpxd dies, vCenter is functionally down: no provisioning, no vMotion orchestration, no DRS, no HA reconfiguration. VMs already running on hosts keep running, and FDM still restarts them after a host failure, because HA does not depend on vpxd.

VMware vCenter Server Monitoring

Mon, 01 Jan 0001 00:00:00 +0000

VMware vCenter Server Monitoring

What Is VMware vCenter Server?

VMware vCenter Server is a centralized platform for managing VMware vSphere environments. It allows administrators to automate and deliver a virtual infrastructure with confidence. vCenter Server provides essential vSphere and ESXi host management capabilities for IT teams.

Monitoring VMware vCenter Server With Netdata

Netdata offers a real-time monitoring solution for VMware vCenter Server with its robust vSphere collector. This powerful tool allows you to track host and virtual machine (VM) performance statistics, providing valuable insights into your virtual environments.

VMware vSphere Operations Guides

Mon, 01 Jan 0001 00:00:00 +0000

How vSphere and vCenter actually fail in production, what the early warning signals look like, and the runbooks for the symptoms you’ll see in real incidents — across both the ESXi data plane and the vCenter management plane.

vSphere 'Virtual machine disks consolidation is needed': clearing the warning without stunning the VM

Mon, 01 Jan 0001 00:00:00 +0000

The “Virtual machine disks consolidation is needed” warning means the VMkernel left delta VMDKs on the datastore after a snapshot delete that did not fully commit. The VM is still running, but its writes are going through delta files that were never meant to persist.

The warning is set by VirtualMachine.runtime.consolidationNeeded in the vCenter inventory. It is distinct from the Snapshot Manager view: a VM can have this flag set while showing zero snapshots in the manager, because the flag tracks orphaned files on the datastore, not the snapshot tree.

vSphere CPU ready time high (%RDY): VMs starved while the guest looks idle

Mon, 01 Jan 0001 00:00:00 +0000

A database VM takes twice as long to run its nightly batch. Application latency pings fire. You SSH into the guest, run top, and CPU utilization sits at 25%. Memory is fine. Disk I/O looks normal. Nothing inside the VM explains the slowdown.

This is the classic signature of CPU ready time in vSphere. The guest OS has no visibility into hypervisor scheduling decisions. When the ESXi CPU scheduler cannot find a free physical CPU for a runnable vCPU, the vCPU waits in the READY state. The guest never learns it was descheduled, so from inside the VM everything looks idle while the hypervisor sees a starved VM.

vSphere HA 'Insufficient resources to satisfy configured failover level': admission control

Mon, 01 Jan 0001 00:00:00 +0000

The error “Insufficient resources to satisfy configured failover level for vSphere HA” is admission control refusing a VM power-on, vMotion, or reservation change because granting it would leave the cluster without enough spare capacity to honor the configured HA failover policy. Admission control is doing its job: protecting the restart guarantee after a host failure.

The cluster may physically hold more capacity than admission control lets you commit. A cluster with 500 GHz of CPU and 2 TB of RAM may only let you deploy against roughly 70% of that, with the rest held in reserve so HA can restart protected VMs after a host failure. Operators who bought hardware expecting to use all of it hit this wall during provisioning and reach for the disable switch.

vSphere host swapping (SWCUR/SWW/s): hypervisor swap and the memory death spiral

Mon, 01 Jan 0001 00:00:00 +0000

When SWR/s is sustained above zero on an ESXi host, the VMkernel is actively reading VM memory pages back from .vswp files on the datastore. That is not a warning state. It is an active performance emergency. Every swapped-in page costs roughly 100x DRAM latency, and the swap I/O itself competes with VM disk I/O on the same datastore, producing a double penalty that degrades every VM on the host simultaneously.

vSphere memory ballooning (MCTLSZ): the host is reclaiming guest RAM

Mon, 01 Jan 0001 00:00:00 +0000

You open esxtop, switch to the memory view, and a VM’s MCTLSZ column is no longer zero. A few hundred megabytes or several gigabytes, the VMkernel has inflated the vmmemctl balloon driver inside that guest and is forcing the guest OS to hand back memory it thought it owned. From the host’s perspective this is gentle reclamation. From the guest’s and the application’s perspective, it is often the start of a silent performance decline.

vSphere monitoring checklist: the signals every host, VM, and vCenter needs

Mon, 01 Jan 0001 00:00:00 +0000

Send this to someone standing up vSphere monitoring for the first time, or rebuilding an alerting setup that pages too often and misses real incidents. It lists the signals worth collecting across the hypervisor plane (ESXi hosts and VMs) and the management plane (vCenter Server Appliance).

vSphere does not fail like a generic Linux box. CPU contention is invisible from inside the guest. Memory goes from fine to catastrophic in minutes once host swapping starts. A datastore at 99% full looks identical to one at 5% full from inside a VM, until every VM on it halts. And vCenter can degrade for weeks before anyone notices, because DRS, HA, and the API quietly keep working until they don’t. Generic CPU/disk/network dashboards miss most of this.

vSphere PSOD (purple screen of death): diagnosing an ESXi host crash

Mon, 01 Jan 0001 00:00:00 +0000

A purple screen of death (PSOD) is the ESXi VMkernel’s deliberate halt. When the kernel detects an unrecoverable condition, an uncorrectable machine check, a driver panic, or a corrupted data structure, it stops the host on purpose, paints the purple diagnostic screen, and writes a core dump if a target is configured. Every VM on that host dies instantly. There is no graceful shutdown and no live migration off the host.