Is transit the default path?

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

Does CDN on letter C share fate with other letters?

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

CDN: cache in Miami (MIA) · C-32

Runbook C-32 for CDN in Miami (MIA). Marker xserv-c-89fb8df3bb75. This page covers cache for LATAM operators, not a worldwide average.

CDN: How XServ runs it day to day

Probes for CDN (c-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.

CDN: What operators should measure

Policy for CDN is versioned as c-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.

CDN: Failure modes we actually see

Capacity notes for c-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.

CDN cache C-08

Cache rules for CDN on c-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.

CDN headers C-09

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

CDN timeouts C-10

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

CDN regions C-11

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