Ceph

what does it mean?

osd            object storage daemon
rados          Reliable Autonomic Distributed Object Store
rbd            Rados Block Device

ceph

Status of ceph

ceph -s

Disk usage

ceph df

Check placement group stats

ceph pg dump

View the CRUSH map

ceph osd tree

Get du from block devices in pool named *rbd*

POOL=$(ceph osd pool ls | grep rbd) ; for i in $(rbd -p $POOL ls | xargs) ; do echo $POOL $i ; rbd -p $POOL du $i 2>/dev/null ; done

access ceph in odf

oc rsh -n openshift-storage $(oc get pods -n openshift-storage -o name -l app=rook-ceph-operator)
export CEPH_ARGS='-c /var/lib/rook/openshift-storage/openshift-storage.config'

list osd pools

ceph osd pool ls
ceph osd pool autoscale-status
ceph config dump
# disable autoscaling
ceph osd pool ls | while read i ; do echo '*' $i ; ceph osd pool set $i pg_autoscale_mode off ; done
# Look to see how much data is being used for pg:s.
# Number of PGLog Entries, size of PGLog data in megabytes, and Average size of each PGLog item
for i in 0 1 2 ; do echo '*' $i ; osdid=$i ; ceph tell osd.$osdid dump_mempools | jq -r '.mempool.by_pool.osd_pglog | [ .items, .bytes /1024/1024, .bytes / .items ] | @csv' ;done
ceph df