Guance Learn

Observability questions

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

Illustration of scheduled jobs, logs and Linux operations
Explainer

Fix a missing newline at the end of a crontab

Find and repair the missing final newline without confusing user crontabs with system cron files.

  • Engineering
  • Explainer
3 min read
Illustration of scheduled jobs, logs and Linux operations
Explainer

Troubleshoot a “bad minute” error in crontab

Find malformed schedule fields, copied characters, and line breaks, and use the syntax checker supported by your cron implementation.

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

Fix curl error 60: unable to get local issuer certificate

Diagnose curl trust-store and certificate-chain failures without disabling verification, including containers, corporate proxies, and Git.

  • Engineering
  • Technical guide
3 min read
Illustration of server operations and request logs
Explainer

What is the default client_max_body_size in Nginx?

Nginx defaults to a 1 MiB request-body limit. Learn where to override it and what other upload limits still apply.

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

Compare one file between two Git commits

Compare a file across Git commits, tags, or branches, inspect word-level changes, and handle renamed paths and three-dot diffs.

  • Engineering
  • Technical guide
2 min read
Illustration of metrics, monitoring, and technical investigation
Explainer

Gauge vs. counter in Prometheus

Choose counters for cumulative events and gauges for current state, then use query functions that match their behavior.

  • Engineering
  • Explainer
2 min read
Illustration of application infrastructure and operations
Technical guide

Laravel Query Builder vs. Collection

Learn when Laravel executes a query, what get(), first(), and paginate() return, and where database filtering differs from Collection operations.

  • Engineering
  • Technical guide
3 min read
py.test vs. pytest: which command should you use? illustration
Explainer

py.test vs. pytest: which command should you use?

Use pytest or python -m pytest for test runs, and understand the legacy py.test entry point and Python import-path differences.

  • Engineering
  • Explainer
2 min read
staticmethod vs. classmethod in Python illustration
Explainer

staticmethod vs. classmethod in Python

Choose a static method for class-related logic without implicit state, or a class method when you need the calling class and subclass-aware construction.

  • Engineering
  • Explainer
2 min read
str() vs. repr() in Python illustration
Explainer

str() vs. repr() in Python

Use str for readable text and repr for diagnostic representations, with examples of escaped strings and custom __str__ and __repr__ methods.

  • Engineering
  • Explainer
2 min read
Illustration of cooperating application modules
Technical guide

Understand ~ and ^ in package.json

Compare npm tilde and caret ranges, including 0.x and prerelease rules, and use a lockfile to record the dependency tree you tested.

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

Filebeat vs. Logstash for sending logs to Elasticsearch

Compare Filebeat collection with Logstash processing, including parsing, outputs, backpressure, and the limits of delivery guarantees.

  • Engineering
  • Explainer
2 min read