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

# AG Redo Queue (KB), Microsoft SQL Server KPI card, Vortex IQ Nerve Centre

> Always On AG only - redo_queue_size from sys.dm_hadr_database_replica_states. Large backlog = secondary falling behind / failover-readiness risk.

**[Nerve Centre KPIs](/nerve-centre/kpi-cards/mssql) · [Audit Profile](/nerve-centre/kpi-cards/mssql/audit) · [Sentiment Settings](/nerve-centre/kpi-cards/mssql/sentiment)**

## At a glance

* **Category:** Replication
* **Type:** Supporting Metrics
* **Chart:** kpi
* **Format:** number
* **Time window:** RT
* **Alert trigger:** >102400 sustained

## Calculation

Always On AG only - redo\_queue\_size from sys.dm\_hadr\_database\_replica\_states. Large backlog = secondary falling behind / failover-readiness risk.

## Known limitations

*Known limitations, FAQs, or reconciliation notes specific to this card. Replace this block when authored.*