storage backup size 30 is insufficient failure when executing storage-backend-add ceph

[Anujeyan Manokeran]

Bug Description : Lab configuration failure when executing cli storage –backed –add ceph replication as below with the failure backup size of 30 is insufficient. Minimum size 40 is required. Root disk for lab is under 240GB.

2018-09-19 18:16:22 [admin@admin]> RUNNING: system storage-backend-add ceph replication=3 min_replication=2 -s cinder,glance,nova --confirmed
backup size of 30 is insufficient. Minimum backup size of 40 is required based on upon glance=10 and database=10 and backup overhead of 20. Rejecting modification request.
2018-09-19 18:16:24 COMMAND FAILED (rc=1): system storage-backend-add ceph replication=3 min_replication=2 -s cinder,glance,nova --confirmed
2018-09-19 18:16:24 ===========================
2018-09-19 18:16:24 Check "/home/wrsroot/lab_setup.group0.log" for more details, and re-run the failed
2018-09-19 18:16:24 command manually before contacting the domain owner for assistance.
controller-0:~$ source /etc/nova/openrc
[wrsroot@controller-0 ~(keystone_admin)]$ system controllerfs-list

+--------------------------------------+-----------------+------+--------------------+------------+-----------+
| UUID | FS Name | Size | Logical Volume | Replicated | State |
| | | in | | | |
| | | GiB | | | |
+--------------------------------------+-----------------+------+--------------------+------------+-----------+
| 287c3d1d-2697-4a67-aee5-272e8bd0a8f4 | backup | 30 | backup-lv | False | available |
| 9d3cb2e2-e9a4-40f6-a80c-fe983702328f | database | 10 | pgsql-lv | True | available |
| 6b379eaa-3c3c-4d69-93d6-3a638a413f07 | extension | 1 | extension-lv | True | available |
| b89a3225-ca20-4a9b-8d6b-f2a9d1f167c1 | glance | 10 | cgcs-lv | True | available |
| 6475e875-08d3-4fb8-9e0e-c83e3f6e315e | gnocchi | 5 | gnocchi-lv | False | available |
| 33ff32ce-648e-4d37-8df4-642f46e70446 | img-conversions | 10 | img-conversions-lv | False | available |
| a8fd129d-b7d5-4110-a644-338e777ed79e | scratch | 8 | scratch-lv | False | available |
+--------------------------------------+-----------------+------+--------------------+------------+-----------+

Severity
--------
Major

Steps to Reproduce
------------------
Follow install procedure
1.Install controller
2.Config controller
3. lab set up to configure during the lab setup.
Below cli failure in lab setup script
system storage-backend-add ceph replication=3 min_replication=2 -s cinder,glance,nova --confirmed
backup size of 30 is insufficient. Minimum backup size of 40 is required based on upon glance=10 and database=10 and backup overhead of 20. Rejecting modification request

Expected Behavior
------------------
Minimum disk size should be supported. No failure

Actual Behavior
----------------
As per description

Reproducibility
---------------
100% reproducible

System Configuration
--------------------
Storage system

Branch/Pull Time/Commit
-----------------------
Master build of 2018-09-18_20-18-0

Timestamp/Logs
--------------
2018-09-19 18:16:24

[Ghada Khalil (gkhalil)]

Targeting stx.2019.03 as this issue only impacts storage systems w/ small disks (240G). The recommended disk size is 500G+

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/604765

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/604766

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/604765
Committed: https://git.openstack.org/cgit/openstack/stx-config/commit/?id=db994ba20f761426c5c79dfa2aa4fd7b77c58a49
Submitter: Zuul
Branch: master

commit db994ba20f761426c5c79dfa2aa4fd7b77c58a49
Author: Stefan Dinescu <email address hidden>
Date: Mon Sep 24 15:34:02 2018 +0300

    Change backup partition size for small disks

    Minimum backup partition size is calculated as the sum between the
    sizes of the glance and database partitions, as well as a 20GB
    overhead.

    This fix increase the default backup size partition to 40GB to
    be in line with the above calculations, considering the database
    and the glance partitions are 10GB each by default.

    This also increases the minimum disk requirements from 120GB
    to 130GB.

    Change-Id: I15396c92136562188f9cdf82afa473361cb45aeb
    Closes-bug: 1793543
    Signed-off-by: Stefan Dinescu <email address hidden>

[Ghada Khalil (gkhalil)]

Only one of the two required commits is merged; re-opening until the second commit is merged as well.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/604766
Committed: https://git.openstack.org/cgit/openstack/stx-metal/commit/?id=bea3956ee912abaa2950dc8b3de58092fba0fea1
Submitter: Zuul
Branch: master

commit bea3956ee912abaa2950dc8b3de58092fba0fea1
Author: Stefan Dinescu <email address hidden>
Date: Mon Sep 24 15:21:34 2018 +0300

    Change backup partition size for small disks

    Minimum backup partition size is calculated as the sum between the
    sizes of the glance and database partitions, as well as a 20GB
    overhead.

    This fix increase the default backup size partition to 40GB to
    be in line with the above calculations, considering the database
    and the glance partitions are 10GB each by default.

    This also increases the minimum disk requirements from 120GB
    to 130GB.

    Change-Id: I5cfc329870a84a6245d868b4c4990829e702e886
    Closes-bug: 1793543
    Signed-off-by: Stefan Dinescu <email address hidden>