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## Overview

Root volume (OSD and MON store) is dangerously full. You should increase the space available to the node. The default location for the store sits under /var/lib/rook/ as a `hostPath` volume.

## Steps for debugging

### Check node low on disk space

``````$ceph_cluster_ns=syn-rook-ceph-cluster$ ceph_mon_name=a (1)
$kubectl -n${ceph_cluster_ns} get deploy -lapp=rook-ceph-mon,mon=\${ceph_mon_name}  -ojson | jq '.items[].spec.template.spec.nodeSelector'
{
"kubernetes.io/hostname": "storage-XXXX" (2)
}``````
 1 The name of the monitor that’s alerting. 2 The node that the monitor is running on.

### Increase the size of the node’s disk

Increase the size of the node’s disk according to your cloud provider’s documentation.