Kibana: การแสดงผลและแดชบอร์ด

Welcome to Kibana! It's the "K" in the ELK Stack, serving as your window into the data stored in Elasticsearch. Kibana is a powerful open-source tool for data visualization and exploration.

It allows you to query, analyze, and visualize your Elasticsearch data, helping you uncover insights and monitor the health of your systems.

When you first open Kibana, you'll see a navigation menu on the left. Key sections include:

• Discover: Explore raw data, search, and filter.
• Visualize: Create individual charts and graphs.
• Dashboard: Combine multiple visualizations into a single view.
• Management: Configure indices, users, and settings.

We'll focus on Discover, Visualize, and Dashboard.

The Discover section is where you interact directly with your raw data from Elasticsearch. Think of it as a powerful search engine for your logs or metrics.

• Search Bar: Use Lucene query syntax or KQL (Kibana Query Language) to find specific events.
• Filters: Add interactive filters to narrow down your results.
• Table View: See individual documents (logs) and their fields.

It's crucial for debugging and detailed investigation.

Observability data is time-series data. The time range selector in Kibana (usually top right) is vital for focusing your analysis.

• Quick Selects: "Last 15 minutes," "Last 24 hours," etc.
• Relative Time: "Last 7 days," "Yesterday."
• Absolute Time: Specify exact start and end dates/times.

Choosing the right time range ensures you're looking at relevant data for your investigation.

While Discover shows raw data, Visualize transforms that data into meaningful charts and graphs. Visualizations help you quickly spot trends, anomalies, and patterns that might be hidden in tables of raw data.

Kibana supports a wide array of visualization types, from simple metrics to complex geo maps.

Let's create a simple visualization, like a bar chart showing log counts over time. In the Visualize section:

1. Choose a visualization type (e.g., Vertical Bar).
2. Select your Elasticsearch index pattern.
3. Define your Y-axis (e.g., "Count" aggregation).
4. Define your X-axis (e.g., "Date Histogram" on your timestamp field).

This shows you how many logs occurred in each time interval.

Beyond bar charts, Kibana offers many options to represent your data effectively:

• Line Charts: Great for showing trends over time (e.g., CPU usage).
• Pie Charts: Useful for showing proportions (e.g., error rates by service).
• Data Tables: Display aggregated data in a tabular format.
• Metric Visualizations: Show a single, prominent number (e.g., total errors).

Choose the type that best tells your data's story.

A Dashboard in Kibana is a collection of saved visualizations arranged on a single screen. They provide a high-level overview of your system's health, performance, or specific application metrics.

Dashboards are dynamic: applying a time filter or a global search to a dashboard updates all its visualizations simultaneously.

Creating a dashboard is straightforward:

1. Navigate to the Dashboard section.
2. Click "Create new dashboard."
3. Click "Add" and select your saved visualizations from the list.
4. Arrange and resize them as needed.

You can also add new visualizations directly from the dashboard view. This allows for quick, comprehensive monitoring.

In this lesson, we explored Kibana, the visualization layer of the ELK Stack. You learned to:

• Use Discover for raw data exploration.
• Create various charts in Visualize.
• Combine these into insightful Dashboards.

Kibana empowers you to transform vast amounts of data into actionable insights, making your systems more understandable and observable. Next, we'll dive into advanced ELK techniques!