# MongoDB: WiredTiger error (28) [...] No space left on device / Fatal assertion 28558 ... disk full

**Code:** `WiredTiger: No space left on device` · **Category:** MongoDB · **Seen on:** MongoDB, Linux

MongoDB ran out of disk space on the data volume and stopped or refuses writes.

## Meaning

Free space immediately (old logs, other files), expand the volume, then restart. Drop unused collections/indexes, compact (`compact` or resync the node), and add monitoring/alerts at 80% disk. Journal and `diagnostic.data` can be large; rotate logs with `logRotate`.

## Common causes

- Data volume full
- Logs/diagnostic data growth
- Unbounded collections (TTL missing)
- Oplog or temp files for large sorts
- Backups stored on the same disk

## Quick fix

1. Free space: delete old logs/backups, expand disk
2. Restart `mongod` after freeing space
3. Add TTL indexes and retention; monitor disk

## Detailed fix by platform

### Linux

1. `df -h /var/lib/mongodb && du -sh /var/lib/mongodb/* | sort -h | tail && sudo journalctl -u mongod -n 30`

## How to diagnose

1. **Disk** — Used %?
2. **Largest** — What consumes?
3. **Retention** — TTL?

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Source: [WhatIsMyError](https://whatismyerror.com/errors/mongodb/wiredtiger-no-space-left)