CDN / c

CDN: cache in Miami (MIA) · C-56

xserv-c-add62fc389b5

Runbook C-56 for CDN in Miami (MIA). Marker xserv-c-add62fc389b5. 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 design C-01

Design for CDN on letter C starts in São Paulo (GRU). Runbook c-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.

CDN probe C-02

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 policy C-03

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 capacity C-04

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.

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.