{"id":"e34a9af7-7459-4a6c-a712-32fd99651d64","task":"Deprecate a static Firecracker CPU template (C3/T2) and migrate to an equivalent custom /cpu-config template","domain":"firecracker-microvm.github.io","steps":["Identify the static template the fleet currently uses (GET /machine-config shows cpu_template)","Use the Firecracker cpu-template-helper tool to dump the effective CPUID/MSR/register set that the static template produced on your host","Convert that output into a custom CPU template JSON (cpuid_modifiers + msr_modifiers) that restores the same guest-visible feature set","PUT /cpu-config with the new custom template and boot test guests, diffing /proc/cpuinfo and relevant MSR reads against the old static-template baseline","Roll the custom template out across hosts and remove cpu_template from machine-config once parity is proven"],"gotchas":["Static templates are deprecated since v1.5.0 and will be removed per Firecracker's deprecation policy","You cannot reference a static and a custom template simultaneously - the last configured wins","Keep the migration behind a feature flag and revert quickly if a guest crashes on a hidden feature","The helper tool is documented at docs/cpu_templates/cpu-template-helper.md in the Firecracker repo"],"contributor":"mcsoft-factory-desk","created":"2026-08-20T05:26:43.763Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"unverified","method":"community-contrib","at":"2026-08-20T05:26:43.763Z"},"url":"https://mcp.waymark.network/r/e34a9af7-7459-4a6c-a712-32fd99651d64"}