{ "uid": "cogitave.learn.install-the-massar-agent.knowledge-check", "kind": "moduleUnit", "href": "/modules/install-the-massar-agent/knowledge-check/", "title": "Knowledge check", "summary": "", "type": null, "products": [], "roles": [], "levels": [], "subjects": [], "headings": [], "source": "", "partOf": "cogitave.learn.install-the-massar-agent", "durationInMinutes": 4, "quiz": { "title": "Check your knowledge", "questions": [ { "content": "Which statement about how install.sh verifies the massar-agent binary before installing it is accurate?", "choices": [ { "content": "The SHA-256 checksum is verified unconditionally; the cosign signature check runs only if cosign is installed and --skip-signature was not passed.", "isCorrect": true, "explanation": "Correct. The checksum check has no off switch. The cosign step is skipped with a warning if cosign isn't found, and skipped outright if --skip-signature was passed." }, { "content": "Both the checksum and the signature check are skipped entirely when --skip-signature is passed.", "isCorrect": false, "explanation": "Incorrect. --skip-signature only skips the cosign signature step. The SHA-256 checksum is always verified, with or without that flag." }, { "content": "If cosign isn't installed on the machine, the installer refuses to continue.", "isCorrect": false, "explanation": "Incorrect. If cosign is missing, install.sh prints a warning and continues on the verified checksum alone - it does not abort the install." } ] }, { "content": "Where does install.sh write the agent's runtime configuration on Linux, and how is it protected?", "choices": [ { "content": "/etc/massar/agent.env, created under a strict umask and then chmod 0600.", "isCorrect": true, "explanation": "Correct. The directory is 0750 and the env file itself is written under umask 077 and explicitly set to 0600 - readable only by root, because it holds the device's token." }, { "content": "/etc/systemd/system/massar-agent.service, mode 0644.", "isCorrect": false, "explanation": "Incorrect. That path is the systemd unit file, which only references the config via EnvironmentFile - it does not itself contain the token, and world-readable is fine for a unit file." }, { "content": "$HOME/.config/massar/agent.env, readable by the invoking user.", "isCorrect": false, "explanation": "Incorrect. Configuration is written system-wide under /etc/massar, not per-user - the service runs under a systemd DynamicUser, not any interactive account's home directory." } ] }, { "content": "Building with cargo build --features dev-tools unlocks two additional binaries used only to prove the relay locally, without Diyar. What are they?", "choices": [ { "content": "massar-broker-dev and massar-op-test.", "isCorrect": true, "explanation": "Correct. Both are declared required-features = [\"dev-tools\"] in the agent crate's Cargo.toml: a dev-only broker and an automated operator test client." }, { "content": "massar-agent and massar-broker-dev.", "isCorrect": false, "explanation": "Incorrect. massar-agent is the binary you'd actually install on a device - it builds and runs without the dev-tools feature at all." }, { "content": "massar-broker-dev and massar-diyar-mock.", "isCorrect": false, "explanation": "Incorrect. There is no massar-diyar-mock binary. The operator-side test client is massar-op-test." } ] }, { "content": "Which pair correctly matches an OS to its supported removal path?", "choices": [ { "content": "Linux: sudo ./uninstall.sh. Windows: Settings > Apps > Cogitave Massar > Uninstall, or running uninstall.ps1 directly.", "isCorrect": true, "explanation": "Correct. install.sh points you at sudo ./uninstall.sh when it finishes; on Windows the installer copies uninstall.ps1 into the install directory and wires it into Settings > Apps, so you can remove Massar from the OS's own uninstall surface or by running the script directly." }, { "content": "Linux: rm -rf /opt/massar. Windows: delete the .exe from Program Files by hand.", "isCorrect": false, "explanation": "Incorrect on both counts. Massar installs to /usr/local/bin and /etc/massar on Linux, not /opt; and deleting the Windows .exe by hand leaves the service and the Settings > Apps entry still registered." }, { "content": "Both: re-run the installer with an --uninstall flag.", "isCorrect": false, "explanation": "Incorrect. Neither install.sh nor install.ps1 has an --uninstall flag - removal is a separate uninstall.sh / uninstall.ps1 script." } ] }, { "content": "The release pipeline's verify-install job runs against every freshly built release. What does it actually do?", "choices": [ { "content": "It runs install.sh --verify, then downloads the just-built massar-agent-linux-x86_64 binary, checksum-verifies it, marks it executable, and asserts it runs - proving the install path works against the real artifact before the release is trusted.", "isCorrect": true, "explanation": "Correct. That is exactly the verify-install job: a clean-room check that the installer's preflight passes and the freshly published binary can be fetched, verified, and run (mirroring namzu's consumer gate)." }, { "content": "It performs the full systemd service install and opens a live session to a Diyar broker to confirm an operator can connect.", "isCorrect": false, "explanation": "Incorrect. verify-install does not stand up the service or reach a real broker - the job's own comment notes a full service install needs the real broker, so it only asserts the binary is fetched, verified, and runnable." }, { "content": "It uninstalls the agent and asserts every file and the service are gone, because removal is the release gate.", "isCorrect": false, "explanation": "Incorrect. The verify-install job proves the install and download path, not removal - it never runs the uninstaller. Each installer ships a matching uninstall script, but that is not what this CI gate checks." } ] } ] } }