====== [HOWTO] Completely remove OSD from cluster ======
^ Documentation ^|
^Name:| [HOWTO] Completely remove OSD from cluster |
^Description:| HOW TO Completely remove OSD from cluster (hardcore edition) |
^Modification date :|07/06/2018|
^Owner:|dodger|
^Notify changes to:|Owner |
^Tags:|ceph, object storage |
^Scalate to:|The_fucking_bofh|
====== Official documentation ======
* [[https://access.redhat.com/solutions/1979363|RH support link]] (you'll need rhnetwork user/pass)
====== Instructions ======
Instructions are copy/paste
===== What are the steps to remove an OSD from an RHCS cluster? =====
There can be various reasons to remove an OSD from an RHCS cluster, and the following steps show how to do it:\\
==== 1. Stop the OSD process ====
sudo /etc/init.d/ceph stop osd.{X} # where {X} is the OSD number
or:
sudo systemctl stop ceph-osd@{X} # where {X} is the OSD number
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==== 2.Mark the OSD out ====
ceph osd out {X} # where {X} is the OSD number
\\
==== 3.Confirm if the OSD is indeed marked out with ====
ceph -w
Important: Wait for data rebalance to complete and all the PG's to come back active+clean, before moving to next steps.
\\
==== 4. [OPTIONAL] Remove the OSD from the crush map ====
Step 4 is only needed if OSD is getting permanently removed from the cluster and will not be redeployed
ceph osd crush remove osd.{X}
If OSD is being redeployed and because of that need removal then skip step 4 it will keep OSD in the CRUSH map as DNE and will not cause data rebalance because of CRUSH map update. Only addition of OSD will cause data movement.
\\
==== 5.Remove the authentication key for the OSD ====
ceph auth del osd.{X}
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==== 6.Confirm that the keys for OSD.{X} are not listed ====
ceph auth list
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==== 7.Remove the OSD from the OSD map ====
ceph osd rm {X}
\\
==== 8.If the procedure is used for replacing the OSD disk then please unmount this osd disk which you want to replace ====
umount /var/lib/ceph/osd/ceph-{x}