Operate the Service

Last updated on 2026-10-04 | Edit this page

Estimated time: 40 minutes

Overview

Questions

  • What does a green monitor actually tell us?
  • How do we release and roll back content locally?

Objectives

  • Interpret the scope of the existing health monitor.
  • Release a local content change and verify it.
  • Roll back through source and explain the limits of that rollback.

Read the monitor before trusting it

At the pointcloud-infra root, read scripts/site-check.sh. It checks the canonical homepage’s status, an exact bare-name redirect, a metadata URL extracted from a collection page (with a supplied Referer), and certificate expiry on both names. It does not execute the viewer or fetch point-cloud binaries.

Running pixi run site-check contacts the live public service. It is optional here; use the following illustrative output for the exercise without contacting that service:

OUTPUT 

ok   https://www.pointcloud.ucla.edu/ -> 200
ok   https://pointcloud.ucla.edu/Iceland/Torfljar.html -> 301 https://www.pointcloud.ucla.edu/Iceland/Torfljar.html
ok   Iceland/Torfljar.html: point cloud metadata loads (200)
FAIL www.pointcloud.ucla.edu: certificate expires in 5 days
Challenge

Choose an operational response

Does this output show a current site outage? What needs attention, and what further test would establish that a visitor can view a scan?

The HTTP checks passed at that moment; the expiry threshold failed before the certificate expired. An operator should investigate renewal and monitor it, not wait for an outage. A browser test must also check JavaScript, CORS, binary requests, and rendering. The output does not prove those work.

Release and roll back in staging

The role’s tasks/content.yml and tasks/release.yml install content in verified release directories, then switch /var/www/pointcloud to the active release. Older releases are pruned according to potree_keep_releases. A source rollback can recreate a release even if the old target directory was pruned, provided its inputs and dependencies remain available.

Challenge

Release a visible change, then restore the previous requirement

Use the Workshop page from the previous episodes. Record its full contents and the current symlink target:

BASH 

podman exec pointcloud-staging readlink /var/www/pointcloud

Change the heading to Workshop collection, release 2. Predict whether Apache needs to reload for this HTML-only change. Converge, inspect the symlink again, and fetch the page. Then restore only your HTML edit in source, converge again, and verify the original heading:

BASH 

pixi run staging-up
podman exec pointcloud-staging readlink /var/www/pointcloud
curl -ksSf https://localhost:8443/Workshop/welcome.html

Finally run pixi run staging-verify and a second converge. Explain what was rolled back, and what was not.

The changed content produces a different archive checksum and release directory. An HTML-only edit does not require an Apache configuration reload. Restoring the previous file and converging republishes the old content through the same role; verify the original heading instead of relying only on the link name or recap.

This rolls back static content. It does not reverse database writes, DOI registration, dependencies, or S3 data changes. Production release and rollback need their own reviewed procedure and acceptance checks.

Finish the public core

Inspect your diff. Remove only the Workshop folder and description you created (or keep them on your learner branch), then converge and verify if you want a baseline staging site. Stop the local container with pixi run staging-down.

You have practiced publication, verification, diagnosis, and a local content rollback. Offline 3D rendering and real-host firewall/SELinux acceptance remain outside this lab. Continue to the separate Dataverse case study, optional AI review exercise, or certification practice.

Key Points
  • Monitors provide bounded evidence, including early warnings.
  • Verify a release with a requirement-specific check.
  • Static-content rollback does not establish data-migration rollback safety.