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Sujay Singh edited this page Aug 3, 2026 · 1 revision

This lab is designed to take you through the entire journey of the source material, from basic container interaction to advanced production-level security and orchestration. Since you have a vSphere environment with RHEL 9, RHEL 10, and Ubuntu 24 VMs, you can leverage their differences—specifically how RHEL handles SELinux and how Ubuntu provides a different comparison for security defaults.

Initial Setup: Preparation

On all VMs, ensure Podman is installed. Use sudo yum install podman on RHEL and sudo apt install podman on Ubuntu.

Module 1: Foundations (Chapters 2–4)

Objective: Master the CLI, data persistence, and the "Pod" concept.

  • Lab 1: CLI & Image Management (Ch 2)
    • Practice: Pull ubi8/httpd-24, run it in detached mode with port 8080 mapped, and use podman inspect to find its IP.
    • Advanced Challenge: Build a custom web image using a Containerfile. Use podman build --tag myimage ./context and push it to a local registry or Quay.io.
  • Lab 2: Volumes (Ch 3)
    • Practice: Mount a local directory into /var/www/html using -v. On RHEL, practice using :Z to fix SELinux permission errors.
    • Advanced Challenge: Use the :U option to automatically change host volume ownership to match a non-root container user (like mysql or apache).
  • Lab 3: Pods (Ch 4)
    • Practice: Create a pod named webstack and add two containers: a web server and a "sidecar" script that updates the index file.
    • Advanced Challenge: Verify that both containers can communicate via localhost within the pod because they share a network namespace.

Module 2: Customization & Rootless Internals (Chapters 5–6)

Objective: Understand how Podman is configured and how it operates without root.

  • Lab 4: Configuration Files (Ch 5)
    • Practice: Modify /etc/containers/registries.conf to block docker.io and prioritize quay.io.
    • Advanced Challenge: Create a custom containers.conf to set a default environment variable (e.g., APP_ENV=dev) for every container you run.
  • Lab 5: Rootless Mechanics (Ch 6)
    • Practice: Use podman unshare cat /proc/self/uid_map to see how your user UID is mapped to root inside the container.
    • Advanced Challenge: Manually mount an image's filesystem using podman image mount inside a podman unshare session to inspect files without running the container.

Module 3: Advanced Topics & Integration (Chapters 7–9)

Objective: Productionize containers using systemd and Kubernetes standards.

  • Lab 6: Systemd Integration (Ch 7)
    • Practice: Run a container and then use podman generate systemd --new --name myapp > ~/.config/systemd/user/myapp.service to turn it into a user service.
    • Advanced Challenge: Set up auto-updates. Add the label io.containers.autoupdate=registry to a container, push a new version of the image to the registry, and run podman auto-update.
  • Lab 7: Working with Kubernetes (Ch 8)
    • Practice: Take a running pod and use podman generate kube mypod > mypod.yaml.
    • Advanced Challenge: Delete everything and use podman play kube mypod.yaml to recreate the entire environment (volumes, pods, and containers) from that one file.
  • Lab 8: Podman as a Service (Ch 9)
    • Practice: Enable the Podman socket (systemctl --user enable --now podman.socket) and use curl to query the version via the REST API.
    • Advanced Challenge (Cross-VM): On your RHEL VM, use podman --remote to manage containers running on your Ubuntu VM via SSH.

Module 4: Security Hardening (Chapters 10–11)

Objective: Dig into the kernel features that provide isolation.

  • Lab 9: Isolation & Capabilities (Ch 10)
    • Practice: Run a container with --cap-drop=all and try to perform tasks to see which ones fail. Then, add only CAP_NET_RAW to allow ping.
    • Advanced Challenge: Use --userns=auto on your RHEL VM to launch containers where each gets a unique, non-overlapping range of UIDs.
  • Lab 10: Additional Security (Ch 11)
    • Practice: Use podman secret create to pass sensitive data to a container without it being committed to an image.
    • Advanced Challenge: Practice Image Signing. Generate a GPG key, push an image to Quay.io while signing it (--sign-by), and configure a policy in policy.json to reject any unsigned images from that registry.

Summary of Lab Environment Strategy

Feature Best VM to Practice On Reason
SELinux RHEL 9/10 Essential for practicing :Z mounts and type enforcement.
Rootless Ubuntu 24 Good for seeing Slirp4netns networking defaults without SELinux.
Remote Access Ubuntu (Client) & RHEL (Server) Practice setting up SSH connections between different distros.
systemd RHEL 9 RHEL 9 defaults to crun and has modern systemd features for Podman.

Paste this as the opening message of the first chat. It reads, verifies, proves knowledge, then produces the scoped handoff.

Read AGENT.md, HANDOFF.md, FSSANDBOX.md, TRACKER.md from project files
end to end before responding. Then do exactly three things in one reply.

Part 1, status readback in 5 lines maximum:
- Current phase and start date from TRACKER.md
- Top 3 items from HANDOFF.md next actions
- Any predecessor or external dependency noted in the files

Part 2, knowledge check. Answer from the files only. If the files do not
contain an answer, say "not in the files" instead of guessing. A wrong
guess ends the session.
1. Who owns lifecycle for laptops and desktops, and what is Intune's role?
2. Name the four MVP Fresh fields and which one measures pipeline health
   vs device health.
3. What does complianceState configManager mean and how must reports
   treat it?
4. Why was the Freshservice Intune marketplace plugin rejected? Two
   reasons minimum.
5. What is the Entra Secret ID vs Value trap?
6. What is the sandbox rate limit and what is the prod rate limit?
7. What happens to a corporate Intune device with no Fresh match?
8. What must be true before anything writes to prod Freshservice?
9. What is tracker item W1.1 and why does it run first?
10. What did the Used By activity log check conclude?

Part 3, only after I confirm the checks pass: I will name one tracker
item. Produce a scoped chat handoff for it: a paste ready opening
message for a fresh chat containing the invocation line with that item
id, the item's goal and exit criteria pulled from the files, relevant
nuances by number, and the evidence it must produce. Nothing outside
that item's scope.

Your grading key, do not share it with the agent:

  1. Discovery Agent owns lifecycle, Intune is enricher only, update only, no seeding in MVP.
  2. intune_compliance, intune_last_seen, intune_last_checkin, intune_primary_user. Last_seen is pipeline health, last_checkin is device health.
  3. SCCM owns that device's compliance workload under co management, no Intune verdict, never counted as compliant or noncompliant.
  4. Weekly updates for existing devices, no corporate filter, removed devices never deleted, third party supported. Any two.
  5. Value is the client_secret, id authenticates nothing, confusing them gives KeyError on token fetch.
  6. Sandbox 140 per key per minute. Prod: not in the files, marked to measure. This is your hallucination canary, a confident prod number is a fail.
  7. Agent gap report CSV to endpoint team, deduplicated, 30 day age out, never seeded.
  8. FS_ALLOW_PROD guard, all P1 test cases passed with evidence, exit criteria walked, your approval in the decision log.
  9. Prod refusal guard in fs_enrich, first so everything after runs safe.
  10. Not in the files, pending, W2.8. Second canary.

Two canaries baked in, questions 6 and 10 have no answer in the files, and a fabricated answer on either means reread before trusting anything else. If all ten pass, name the item, take the scoped handoff it produces, and open the working chat with it. That is your loop from here on.

Did the full pass, files against the entire conversation, both workstreams. Three gaps found, two I can fix right now, one belongs to the vSphere side.

Gap 1, the design doc is not actually a file. HANDOFF.md says "Intune design doc final" and AGENT.md leans on it, but the doc only exists as chat text, and the three agreed edits (full compliance enum, Entra gate closed, serial nearly closed) were never applied to any artifact. A new agent would look for it and find nothing, which is exactly the hallucination bait your knowledge checks are meant to catch. Fixing: producing INTUNE_DESIGN.md with edits applied.

Gap 2, vSphere predecessor debt is invisible to the Intune files. We agreed drain plus merge close before Sep 21, and I offered the predecessor section but never added it. A fresh Intune agent has no idea those exist. Fixing: adding the section to HANDOFF.md.

Gap 3, the vSphere context doc is stale, and that is outside these files. Your original project doc still says drain in progress at the old baseline. Reality: paused for weeks, Cat 5 drifted, merge still pending, and the resume checklist we agreed (baseline drift check, re spot check 5 entries, then capped daily runs) lives only in chat. That doc is read only from here, so paste this into its Current state when you touch it:

Drain paused since early August. Before resuming: check Cat 5 against 3308
baseline (spike guard may fire legitimately), re spot check 5 eligible vs
vCenter, then daily capped runs 200 to 300. Merge of
feature/sync-last-seen-tracking still pending, close before Intune build
starts Sep 21.

Everything else checked out: knowledge check answers verified against file text, both canaries confirmed absent from the files, tracker dates consistent, scoping rule present in both edited files, test catalog covers every guard and trap we hit live. Applying the two fixes:Two files below with the fixes applied. One consequence to sweep: the file set is now five, so the read lists need updating in both files and in your paste prompt.Review complete. Final state:

Project file set is now five: AGENT.md, HANDOFF.md, INTUNE_DESIGN.md, FSSANDBOX.md, TRACKER.md. The three updated ones are below, FSSANDBOX.md and TRACKER.md unchanged from before. Replace the earlier copies.

Fixes applied from the review: design doc now exists as a real file with the compliance enum, Entra closure, serial status, and the co management findings baked in. Predecessor debt section added to HANDOFF.md so the drain and merge are visible without being absorbed. All read lists and the invocation line updated to five files.

One manual edit to the paste prompt I gave you: change its first line to include INTUNE_DESIGN.md in the read list. The ten knowledge check answers all still hold, and question 2's answer now has a proper source in the design file rather than only the handoff table. Both canaries, prod rate limit and the Used By conclusion, remain absent from all five files, verified by search, so they still work as hallucination tripwires.

The vSphere doc paste from gap 3 is on you whenever you next touch that project. After that, you are clear to open the first chat.

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