VMware tutorial - IT technology blog

Configuring vSphere Alarms and Email Notifications: Automated SysAdmin Alerts When ESXi CPU, RAM, and Datastore Exceed Thresholds

A comparison of three ESXi monitoring approaches (native alarms, Zabbix, PowerCLI) and a practical walkthrough for deploying vSphere Alarms to automatically email SysAdmins when CPU, RAM, or Datastore usage hits dangerous thresholds. Step-by-step from SMTP configuration to fine-tuning thresholds to avoid alert fatigue.
Monitoring tutorial - IT technology blog

Monitoring Elasticsearch and OpenSearch Clusters with Prometheus Exporter and Grafana: Tracking Index Health, Query Latency, and System Resources

A practical guide to monitoring Elasticsearch and OpenSearch clusters with Prometheus Exporter and Grafana, covering a comparison of approaches, elasticsearch_exporter setup, and alert configuration for JVM heap, unassigned shards, and disk watermark. Hard-won lessons from 6 months running 50 million documents in production.
CentOS tutorial - IT technology blog

Production-Ready KVM/QEMU Setup on CentOS Stream 9: Bridge Network, SELinux, and firewalld Done Right

A default KVM setup is easy — but production requires more. This article focuses on three commonly overlooked areas: bridge networking with nmcli instead of the default NAT, proper SELinux context configuration instead of disabling it, and firewalld FORWARD rules to get VM traffic working. Includes remote Virt-Manager management over SSH and troubleshooting common errors.