Routing / r
Routing: design in São Paulo (GRU) · R-49
xserv-r-4b75e12dd8d3
Runbook R-49 for Routing in São Paulo (GRU). Marker xserv-r-4b75e12dd8d3. This page covers design for LATAM operators, not a worldwide average.
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: What operators should measure
Policy for Routing is versioned as r-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.
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.
Routing timeouts R-10
Timeouts on r-10 are tighter than the WAN RTT to Bogotá. Routing in Santiago fails fast and retries once; a third try needs a human because it is no longer a blip.
- 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.
- Where is Routing measured first?
- From Santiago (SCL) toward Bogotá. A global average is not an SLO for letter R.