> ## Documentation Index
> Fetch the complete documentation index at: https://docs.aviatrix.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Removal of S2C Telemetry Fields and RRD

> Release 9.0 removes two unused Site-to-Cloud telemetry fields and the Round-Robin Database from the Controller. No user action required.

Release 9.0 removes two unused Site-to-Cloud (S2C) telemetry fields and the
Round-Robin Database (RRD) from the Controller. The change is transparent; no
action is required during or after the upgrade.

## What Changed

### Retired S2C Telemetry Fields

Two telemetry fields that tracked S2C connection usage are removed:

| Field | Description |
| - | - |
| `s2c_st_usage` | Route-based static connections |
| `s2c_bgp_usage` | Route-based BGP connections |

Both fields were instrumented in the Controller but were never used by any
billing plan or reporting workflow. No billing plans, dashboards, or monitoring
workflows are affected by the removal.

### Removed RRD from the Controller

RRD (Round-Robin Database) was a legacy time-series storage mechanism in the
Controller. It was a long-standing source of technical debt and contributed to
Controller stability issues. With the unused S2C telemetry fields retired,
nothing on the Controller still depends on RRD. Release 9.0 removes it.

## Impact

This change is transparent. No action is required during or after the upgrade.

| Concern | Detail |
| - | - |
| Billing or reporting impact | None. The retired fields were never used by a billing plan or reporting workflow. |
| Controller stability | Improved. Removing RRD removes a known source of stability issues. |
| Feature impact | None. No user-facing features depended on these fields or on RRD. |

## Before and After

| Behavior | Before 9.0 | 9.0 |
| - | - | - |
| S2C telemetry fields instrumented | Yes (unused) | Removed |
| RRD present on the Controller | Yes | Removed |
| Billing or reporting impact | None | None |


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