Is transit the default path?

No. Peering in Miami is default; transit to São Paulo is overflow and is billed that way.

Does Routing on letter R share fate with other letters?

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

Routing: docs in Miami (MIA) · R-24

Runbook R-24 for Routing in Miami (MIA). Marker xserv-r-fe87a442e67d. This page covers docs for LATAM operators, not a worldwide average.

Routing: A note on cost and transit

Rollback for r-06 is a documented command, not a hope. Transit is billed as backup while Routing prefers peering in Santiago. If cost spikes, the runbook cuts overflow to Bogotá before touching customer prefixes.

Routing: Why it matters on this continent

Design for Routing on letter R starts in São Paulo (GRU). Runbook r-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.

Routing: How XServ runs it day to day

Probes for Routing (r-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.

Routing rollback R-06

Routing peering R-07

Peering for Routing (r-07) prefers the IX fabric that already carries last-mile ISPs in Bogotá. Session counts and prefix limits are on the same page as the Miami backup path.

Routing cache R-08

Cache rules for Routing on r-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.

Routing headers R-09

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