Downlink Desk Operator's Manual

DMC-DLD-A-10-10-00-00A-400A-AFault isolationIssue 0012026-11-04UnclassifiedQA: UnverifiedApplies to Downlink Desk 0.17.x

SatNOGS link – Fault isolation: data is not being collected

Fault description

One of these alarms is open:

  • No SatNOGS API key on this server yet.

  • SatNOGS rejected the API key.

  • The server hasn't reached SatNOGS since a given time, or has not completed a fetch yet.

You may also have received a phone alert that the last three fetches failed.

Note

Steps marked "on the server" need a terminal on the Downlink Desk server, for example over SSH. If you do not have access, report the alarm to whoever maintains the server.

Preliminary requirements

Required conditions

  • An alert or symptom described above is present.

Required persons

1 × Operator. Estimated time: 10 to 30 minutes.

Support equipment

  • A computer or phone with a web browser, on the same network as the server
  • Terminal access to the server, for example over SSH, for steps marked "on the server"

Supplies

None

Spares

None

Safety conditions

None

Isolation procedure

Step 1

Read the alarm message.

Does it say there is no SatNOGS API key on the server?

Yes go to Result ANo go to Step 2

Step 2

Read the alarm message.

Does it say SatNOGS rejected the API key?

Yes go to Result BNo go to Step 3

Step 3

On the server, read the fetch log: journalctl -u downlink-desk-fetch -n 50.

Does the log say the system clock is behind the newest stored data?

Yes go to Result CNo go to Step 4

Step 4

On the server, check the internet connection: curl -sI https://db.satnogs.org.

Does the command return a response from SatNOGS?

Yes go to Step 5No go to Result D

Step 5

On the server, run a fetch now: cd ~/downlink-desk && .venv/bin/python -m downlink_desk.fetch --force.

Does it finish with a line saying how many new frames were stored?

Yes go to Result ENo go to Result F

Results

Result A

Add the key. Get a SatNOGS DB API key from db.satnogs.org (your avatar, then Settings / API Token). On the server, save it with echo YOURKEY > ~/downlink-desk/secrets/satnogs_token. The next fetch uses it.

Result B

The key is wrong. The most common cause is a SatNOGS Network key instead of a SatNOGS DB key; they are different. The other cause is extra characters pasted with the key. Get the DB key again and save it as in Result A.

Result C

The server's clock has not synced since boot. A Raspberry Pi has no clock battery, so this can happen after a power cut. Check the network connection. The fetch resumes by itself once the clock is set.

Result D

The server has no working internet connection. Check its network cable or Wi-Fi, and the router. Once the connection is back, the next fetch resumes collection.

Result E

Collection is working again. The alarm clears once the console sees a successful fetch. Write a log note with the cause, if known.

Result F

SatNOGS may be unavailable, or may be limiting requests. Downlink Desk waits and retries by itself. Do not shorten the fetch interval: SatNOGS is run by volunteers. Write a log note, check again after the next fetch, and report it if the alarm is still open at handover.

Requirements after job completion

  • The cause is found and recorded in the log, or the alert is handed over with notes.