Sync: design in São Paulo (GRU) · Y-25

Runbook Y-25 for Sync in São Paulo (GRU). Marker xserv-y-f05c3b3555a0. This page covers design for LATAM operators, not a worldwide average.

Sync: Why it matters on this continent

Design for Sync on letter Y starts in São Paulo (GRU). Runbook y-01 keeps a single owner, a written rollback, and a traffic split that can be reversed without a global freeze. Neighbors in Santiago only take overflow after the local pool fails a health window.

Sync: How XServ runs it day to day

Probes for Sync (y-02) leave Santiago every 15s toward Bogotá. XServ pages the named owner if loss or RTT crosses the letter budget. A probe never shares a queue with bulk transfers, so a saturated WAN does not hide a dead PoP.

Sync: What operators should measure

Policy for Sync is versioned as y-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.

Sync headers Y-09

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

Sync timeouts Y-10

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

Sync regions Y-11

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

Sync docs Y-12

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