Does Mesh on letter M share fate with other letters?

The control plane is shared. Data-plane queues for Mesh stay isolated, so incident m-01 cannot drain neighbor letters.

Where is Mesh measured first?

From Santiago (SCL) toward Bogotá. A global average is not an SLO for letter M.

Mesh: design in São Paulo (GRU) · M-49

Runbook M-49 for Mesh in São Paulo (GRU). Marker xserv-m-e22409ad1d88. This page covers design for LATAM operators, not a worldwide average.

Mesh: Why it matters on this continent

Design for Mesh on letter M starts in São Paulo (GRU). Runbook m-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.

Mesh: How XServ runs it day to day

Probes for Mesh (m-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.

Mesh: What operators should measure

Policy for Mesh is versioned as m-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.

Mesh cache M-08

Cache rules for Mesh on m-08 keep language-correct objects near Miami. São Paulo is a sibling cache, not an origin. TTLs are short enough that a bad asset does not live through a weekend.

Mesh headers M-09

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

Mesh timeouts M-10

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

Mesh regions M-11

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