Your First Data
With OneAgent installed, Dynatrace automatically discovers your infrastructure. Let's explore what it found.
Hosts
Every machine with OneAgent appears as a host entity. Query it with DQL:
fetch dt.entity.host
| fields entity.name, monitoringMode, state, tags
🛠 Try it: Open a Notebook (Ctrl+K → "Notebooks" → Create new) → Add a DQL section → Paste the query above → Run it. You'll see your hosts with their monitoring mode and state.
Processes
OneAgent discovers every process running on your hosts:
fetch dt.entity.process_group
| fields entity.name, softwareTechnologies
| limit 10
Each process group shows the detected technology (Java, Node.js, Go, nginx, etc.).
Services
Services are auto-detected from process communication patterns:
fetch dt.entity.service
| fields entity.name, serviceType
| limit 10
Your First Metric
Metrics are time-series data. The timeseries command queries them:
timeseries avg(dt.host.cpu.usage), by:{dt.entity.host}
This returns CPU usage over time for each host. In a Notebook, it automatically renders as a line chart.
Your First Log Query
fetch logs
| filter loglevel == "ERROR"
| fields timestamp, content, loglevel
| sort timestamp desc
| limit 10
⚠️ The field is loglevel (one word), NOT log.level. This is the most common DQL mistake for beginners.
Exploring the Schema
Don't know what fields are available? Use describe:
describe dt.entity.host
This lists every field and its data type. Works for any data object: logs, events, spans, bizevents, dt.entity.service, etc.
Data Objects Reference
Data Object What's In It Example Query
─────────────────────── ────────────────────────────── ──────────────────────────
dt.entity.host Hosts (servers, VMs) fetch dt.entity.host
dt.entity.service Auto-detected services fetch dt.entity.service
dt.entity.process_group Process groups fetch dt.entity.process_group
dt.entity.application RUM web applications fetch dt.entity.application
logs Log records fetch logs
events Davis events and problems fetch events
spans Distributed trace spans fetch spans
bizevents Business events fetch bizevents
💡 Everything in Dynatrace is queryable with DQL. Metrics use timeseries, everything else uses fetch. You'll master both in Track 2.