billing-sync fails every export to the payments API, and no external hostname resolves on the host.
Stage 3 of 4 in Network Response Ladder.
The network migration moved this host to a new subnet, and within minutes billing-sync began logging name resolution failures for the payments API.
The resolver at 10.0.0.1 still answers ping, which convinced the first responder that DNS was fine and the payments provider was down.
The migration notes in /home/user were written in a hurry.
The fix is yours to find: hints, the recovery checks and the debrief unlock inside the incident.
The alert fires and the clock starts. Read the page and the briefing.
Work in a simulated shell with realistic output: logs, configs, services.
Change the system the way you would in production. Hints are there if you get stuck.
Automated checks verify the recovery, then the debrief explains what happened.
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