Cray System Management Documentation > Cray System Management (CSM) Administration Guide > node management > Clear Space in Root File System on Worker Nodes

Clear Space in Root File System on Worker Nodes

The disk space on an NCN worker node can fill up if any services are consuming a large portion of the root file system on the node. This procedure shows how to safely clear some space on worker nodes to return them to an appropriate storage threshold.

Prerequisites

An NCN worker node has a full disk.

Procedure

Check to see if Docker is running.

syctemctl status docker

Example output:

● docker.service - Docker Application Container Engine
   Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled; vendor pres>
   Active: **active** (running) since Wed 2020-06-10 11:03:49 CDT; 2 months 2 days >
     Docs: http://docs.docker.com
 Main PID: 3062 (dockerd)
    Tasks: 145
   CGroup: /system.slice/docker.service
           ├─3062 /usr/bin/dockerd --add-runtime oci=/usr/sbin/docker-runc
           ├─3248 docker-containerd --config /var/run/docker/containerd/contain>
           ├─5557 /usr/bin/docker-proxy -proto tcp -host-ip 0.0.0.0 -host-port >
           └─5576 docker-containerd-shim -namespace moby -workdir /var/lib/dock>

[...]

If Docker is active, proceed to the next step to check its usage.

View the file space usage for Docker.
```
du -sh /var/lib/docker
```
Example output:
```
178G    /var/lib/docker
```
If the output indicates usage is over 100GB, proceed to the next step to prune Docker.
Prune the Docker images.

The until=24 option in the command below preserves data less than one day old.
```
docker image prune -a --filter until=24h
```
Check the usage again with the du -sh /var/lib/docker command.
Prune the Docker volumes.

The until=24 option in the command below preserves data less than one day old.
```
docker volume prune -a --filter until=24h
```
Check the usage again with the du -sh /var/lib/docker command.
Check the usage of /var/log/cray.

Another potentially large consumer of space is /var/log/cray when certain debug flags are enabled.
```
du -sh /var/log/cray
```
Example output:
```
76M     /var/log/cray
```
If the usage is over 20GB, examine the logging and determine if any of the older log information needs to be kept. Candidates for clean up include old imfile-state files, as well as old forwarding-queue files. Reduce the quantity of any additional logging as soon as possible to prevent the disk from filling up again.