Failover / f
Failover: cache in Miami (MIA) · F-80
xserv-f-827859036641
Runbook F-80 for Failover in Miami (MIA). Marker xserv-f-827859036641. This page covers cache for LATAM operators, not a worldwide average.
Failover: How XServ runs it day to day
Probes for Failover (f-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.
Failover: What operators should measure
Policy for Failover is versioned as f-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.
Failover: Failure modes we actually see
Capacity notes for f-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.
Failover cache F-08
Cache rules for Failover on f-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.
Failover headers F-09
Headers for f-09 carry the letter, the region (GRU) and a request id. Failover debugging in São Paulo should not require a packet capture in Santiago first.
Failover timeouts F-10
Timeouts on f-10 are tighter than the WAN RTT to Bogotá. Failover in Santiago fails fast and retries once; a third try needs a human because it is no longer a blip.
Failover regions F-11
Region names on f-11 match DNS and tickets: Bogotá / BOG, with Miami as the documented pair. Failover dashboards never say “LATAM” as if it were one RTT.
- Is transit the default path?
- No. Peering in Miami is default; transit to São Paulo is overflow and is billed that way.
- Does Failover on letter F share fate with other letters?
- The control plane is shared. Data-plane queues for Failover stay isolated, so incident f-01 cannot drain neighbor letters.