Guance Learn

Observability questions

Focused answers for definitions, architecture choices, troubleshooting, pricing, and evaluation.

Linux system logs and server diagnostics
Explainer

Disable TLS 1.0 and TLS 1.1 in Apache

Restrict Apache to supported modern TLS versions, account for virtual-host version boundaries, and verify the result with meaningful handshake tests.

  • Engineering
  • Explainer
3 min read
Illustration of Git branches and version history
Technical guide

Discard unstaged changes in Git

Restore tracked files from the index while keeping staged edits, preview untracked cleanup, or stash changes you may want to recover later.

  • Engineering
  • Technical guide
2 min read
Secure network connections and certificate management
Technical guide

Inspect remote TLS certificates from the command line

Use OpenSSL for certificate details, curl for a quick connection check, or Nmap for an authorized inventory. Keep inspection separate from verification.

  • Engineering
  • Technical guide
3 min read
Illustration of an event loop and asynchronous tasks
Technical guide

Encode and decode Base64 in Node.js

Use Buffer for text or binary data, choose Base64URL when the protocol requires it, and validate external input separately.

  • Engineering
  • Technical guide
3 min read
Illustration of Git branches and version history
Technical guide

Export a Git snapshot without the .git directory

Use git archive to export a commit or subdirectory as ZIP or tar, apply export-ignore rules, and avoid packaging the wrong working-tree contents.

  • Engineering
  • Technical guide
3 min read
Log monitoring illustration
Explainer

Find documents with a missing field in Kibana

Use KQL or Lucene to filter for missing indexed values, and understand why nulls, empty strings, and ignored values behave differently.

  • Engineering
  • Explainer
2 min read
Illustration of Git branches and version history
Technical guide

Download a single directory from GitHub

Use partial clone with sparse checkout to work with one directory, or extract it from an archive when you do not need Git history.

  • Engineering
  • Technical guide
3 min read
Monitoring and troubleshooting illustration
Explainer

Duplicate a Grafana dashboard without overwriting the original

Create a dashboard copy or export and import its JSON, while checking shared library panels, data sources, and alert rules.

  • Engineering
  • Explainer
2 min read
Illustration of server operations and request logs
Explainer

Increase the upload size limit in Nginx

Set client_max_body_size for the right endpoint, allow multipart overhead, and test Nginx and application limits together.

  • Engineering
  • Explainer
3 min read
Illustration of log monitoring and analysis
Explainer

Parse tab-separated fields in Logstash

Use a real tab with the CSV filter or enable configuration escapes explicitly, then verify headers and quoted fields with sample data.

  • Engineering
  • Explainer
2 min read
Illustration of collecting, processing, and monitoring logs
Explainer

Run startup logic with a distroless Fluent Bit container

Choose a compatible shell, a debug image, or a Kubernetes init container for Fluent Bit startup tasks without relying on missing tools.

  • Engineering
  • Explainer
3 min read
Illustration of an event loop and asynchronous tasks
Technical guide

Run an external program from Node.js

Choose execFile for argument-based execution, spawn for streams, or exec for a deliberate shell command, and handle startup and exit failures.

  • Engineering
  • Technical guide
3 min read