Ceph » ceph-volume

I am replacing osd with encryption with this procedure

ceph osd crush reweight osd.30 0.0

ceph osd out 30
service ceph-osd@30 stop
ceph osd crush remove osd.30
ceph auth del osd.30
ceph osd rm 30

mv /var/lib/ceph/osd/ceph-30/ /var/lib/ceph/osd/ceph-30.old/

ceph-volume lvm zap --destroy /dev/sdi
ceph-volume lvm create --data /dev/sdi --dmcrypt

I do not know, why but sometimes this lvm create fails. Last time it failed I got stuck in the loop ceph-volume lvm zap, pvremove (see #47549), ceph-volume lvm create

I saw in the output this dd 10M

When I changed the procedure to
ceph-volume lvm zap, pvremove (see #47549), dd if=/dev/zero of=/dev/sdf bs=1M count=100, ceph-volume lvm create

The osd was successfully created.

I do not know what the difference is between doing a dd with 10M or 100M, but maybe it is worth investigating this.