Is transit the default path?

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

Does Anycast on letter A share fate with other letters?

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

Anycast: capacity in Miami (MIA) · A-40

Runbook A-40 for Anycast in Miami (MIA). Marker xserv-a-6e93e1aebcf3. This page covers capacity for LATAM operators, not a worldwide average.

Anycast: Failure modes we actually see

Capacity notes for a-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.

Anycast: How this letter ties to the rest

Handoff from letter A Anycast into the rest of the platform uses the same request IDs as the gateway. Runbook a-05 names who accepts the ticket after São Paulo pages out. Santiago does not silently inherit the incident.

Anycast: A note on cost and transit

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

Anycast rollback A-06

Anycast peering A-07

Peering for Anycast (a-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.

Anycast cache A-08

Cache rules for Anycast on a-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.

Anycast headers A-09

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