# Redis: MISCONF Redis is configured to save RDB snapshots, but it's currently unable to persist to disk

**Code:** `MISCONF` · **Category:** Redis · **Seen on:** Redis

Redis couldn’t write its RDB snapshot (disk full, permissions, fork failed), so it blocks writes to protect data.

## Meaning

Background save (BGSAVE) failed. Check the Redis log: no space left, wrong ownership of the data directory, or fork failing due to memory overcommit settings.

## Common causes

- Disk full
- Data directory not writable by redis user
- fork() failed (vm.overcommit_memory=0 and low memory)
- Directory changed by CONFIG SET dir

## Quick fix

1. Free disk space / fix directory permissions
2. Set vm.overcommit_memory=1
3. Check the log (/var/log/redis/redis-server.log)

## Detailed fix by platform

### Shell

1. 

```bash
redis-cli CONFIG GET dir
sudo chown -R redis:redis /var/lib/redis
sudo sysctl vm.overcommit_memory=1
redis-cli BGSAVE
```


## How to diagnose

1. **Log** — Reason for failed save
2. **Disk** — df -h
3. **Permissions** — Data dir owner

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Source: [WhatIsMyError](https://whatismyerror.com/errors/redis/misconf-unable-to-persist-to-disk)