# ERR Cluster node timeout exceeded, possible split-brain detected

- **ID:** `redis/cluster-node-timeout-split-brain`
- **Domain:** redis
- **Category:** runtime_error
- **Error Code:** `ERM`
- **Verification:** ai_generated
- **Fix Rate:** 75%

## Root Cause

A cluster node failed to respond within cluster-node-timeout, leading to a potential split-brain scenario where multiple nodes assume master roles.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 6.2 | active | — | — |
| 7.0 | active | — | — |
| 7.2 | active | — | — |

## Workarounds

1. **Run 'CLUSTER FORGET <node-id>' on all healthy masters to remove the unresponsive node, then rejoin it after network recovery.** (80% success)
   ```
   Run 'CLUSTER FORGET <node-id>' on all healthy masters to remove the unresponsive node, then rejoin it after network recovery.
   ```
2. **Configure sentinel monitors with quorum = majority of nodes to prevent split-brain. Example: 'sentinel monitor mymaster 127.0.0.1 6379 2'.** (88% success)
   ```
   Configure sentinel monitors with quorum = majority of nodes to prevent split-brain. Example: 'sentinel monitor mymaster 127.0.0.1 6379 2'.
   ```

## Dead Ends

- **** — Delays detection but does not prevent network partitions; can worsen split-brain. (70% fail)
- **** — May cause data loss if RDB/AOF not synced; does not resolve underlying network issues. (85% fail)
- **** — Split-brain can cause inconsistent data; manual intervention required. (95% fail)