PGs (Placement Groups) are…
To force a scrub on a PG
ceph pg scrub 3.31
ceph pg deep-scrub 3.31
To see the status of PGs on a Ceph node
ceph pg dump pgs_brief
For a more detailed output
ceph pg dump pgs
ceph pg dump pgs | awk '{print $1" "$23}' | column -t