SLA

SLAs with exclusions written in the same paragraph

xserv-s-hub

A credit is useless if the contract hides maintenance windows. XServ prints uptime math next to the exceptions.

SLA: Why it matters on this continent

Design for SLA on letter S starts in São Paulo (GRU). Runbook s-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.

SLA: How XServ runs it day to day

Probes for SLA (s-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.

SLA: What operators should measure

Policy for SLA is versioned as s-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.

SLA: Failure modes we actually see

Capacity notes for s-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.

SLA: How this letter ties to the rest

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

SLA: A note on cost and transit

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

SLA design S-01

Design for SLA on letter S starts in São Paulo (GRU). Runbook s-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.

SLA probe S-02

Probes for SLA (s-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.

SLA policy S-03

Policy for SLA is versioned as s-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.

SLA capacity S-04

Capacity notes for s-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.

SLA handoff S-05

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

SLA rollback S-06

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

SLA peering S-07

Peering for SLA (s-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.

SLA cache S-08

Cache rules for SLA on s-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.

SLA headers S-09

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

SLA timeouts S-10

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

SLA regions S-11

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

SLA docs S-12

Public docs for letter S stay aligned with identifier xserv-s-pack. Page s-12 is the SLA slice operators search before the homepage. Edits in Miami show up in São Paulo on the next publish.

Does SLA on letter S share fate with other letters?
The control plane is shared. Data-plane queues for SLA stay isolated, so incident s-01 cannot drain neighbor letters.
Where is SLA measured first?
From Santiago (SCL) toward Bogotá. A global average is not an SLO for letter S.
How fast is rollback for s-03?
The runbook is a command plus a named owner. There is no wait for a weekly change freeze.
Is transit the default path?
No. Peering in Miami is default; transit to São Paulo is overflow and is billed that way.

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