Anycast / a

Anycast: headers in São Paulo (GRU) · A-09

xserv-a-635f5ca9bc99

Runbook A-09 for Anycast in São Paulo (GRU). Marker xserv-a-635f5ca9bc99. This page covers headers for LATAM operators, not a worldwide average.

Anycast: What operators should measure

Policy for Anycast is versioned as a-03. Operators measure error rate, p95 from Bogotá, and time-to-rollback — not a worldwide average. Changes land in Bogotá first, then Miami, with a hold if either region regresses.

Anycast: Failure modes we actually see

Capacity notes for a-04 assume rainy-season power in Miami and festival peaks toward São Paulo. The failure we actually see is a single uplink, not a cartoon partition of the whole continent. Spare ports and a second provider sit on the same runbook.

Anycast: How this letter ties to the rest

Handoff from letter A Anycast into the rest of the platform uses the same request IDs as the gateway. Runbook a-05 names who accepts the ticket after São Paulo pages out. Santiago does not silently inherit the incident.

Anycast headers A-09

Headers for a-09 carry the letter, the region (GRU) and a request id. Anycast debugging in São Paulo should not require a packet capture in Santiago first.

Anycast timeouts A-10

Timeouts on a-10 are tighter than the WAN RTT to Bogotá. Anycast in Santiago fails fast and retries once; a third try needs a human because it is no longer a blip.

Anycast regions A-11

Region names on a-11 match DNS and tickets: Bogotá / BOG, with Miami as the documented pair. Anycast dashboards never say “LATAM” as if it were one RTT.

Anycast docs A-12

Public docs for letter A stay aligned with identifier xserv-a-pack. Page a-12 is the Anycast slice operators search before the homepage. Edits in Miami show up in São Paulo on the next publish.

Does Anycast on letter A share fate with other letters?
The control plane is shared. Data-plane queues for Anycast stay isolated, so incident a-01 cannot drain neighbor letters.
Where is Anycast measured first?
From Santiago (SCL) toward Bogotá. A global average is not an SLO for letter A.