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How to Configure Deep-Scrubbing

· One min read
Joachim Kraftmayer
Joachim Kraftmayer
Managing Director at Clyso

Ceph cluster health state​

root@clyso-ceph:/home/ceph# ceph -s
  cluster:
    id:     FEBB01CC-4AA5-4C1D-80C4-9D91901467C8
    health: HEALTH_WARN
            256 pgs not deep-scrubbed in time
            266 pgs not scrubbed in time

Admin has noticed that deep-scrubbing has fallen behind.

Possible actions​

If impacting ceph performance is not a concern. osd max scrubs and osd scrub load threshold can be carefully be adapted, but that can have a huge impact on ceph cluster performance.

Show current config​

root@clyso-ceph:/home/ceph# ceph config show osd.1 osd_max_scrubs
1
root@clyso-ceph:/home/ceph#
root@clyso-ceph:/home/ceph# ceph config get osd osd_scrub_load_threshold
0.500000
root@clyso-ceph:/home/ceph#

Set osd_max_scrub​

ceph config set osd_max_scrubs 2

Verify setting​

Ceph config database​

root@ceph-vm-az1-1:/home/kraftmayerj# ceph config get osd osd_max_scrubs
2
root@ceph-vm-az1-1:/home/kraftmayerj#

Ceph osd active settings (osd.1)​

root@clyso-ceph:/home/ceph# ceph config show osd.1 osd_max_scrubs
2
root@clyso-ceph:/home/ceph#

Sources​

osd_max_scrubs

osd_scrub_load_threshold

osd_scrub_during_recovery