> ## 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.

# Nodes Up / Normal (UN), Apache Cassandra KPI card, Vortex IQ Nerve Centre

> Count of endpoints in UN state from nodetool status / system.peers. Cassandra-defining - DN node = reduced replica availability.

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

## At a glance

* **Category:** Executive Overview
* **Type:** Key Metrics
* **Chart:** kpi
* **Format:** number
* **Time window:** RT
* **Alert trigger:** \< expected (any DN node)

## Calculation

Count of endpoints in UN state from nodetool status / system.peers. Cassandra-defining - DN node = reduced replica availability.

## Known limitations

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