mariaDB 10.1 boostrap failed

[xinliang]

MariaDB 10.0 and 10.1 are different:
1, 10.1 integrated Galera cluster feature[1].
2, 10.1 integrated MariaDB Backup which similar to Percona XtraBackup[2] starting with MariaDB 10.1.23.

Current kolla/kolla-ansible only support MariaDB 10.0 not 10.1.

[1] https://mariadb.com/kb/en/library/getting-started-with-mariadb-galera-cluster/
[2] https://mariadb.com/kb/en/library/mariadb-backup-overview/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/529505
Committed: https://git.openstack.org/cgit/openstack/kolla-ansible/commit/?id=7377846f8a4e2f88f412018fb20c792b1abcea4a
Submitter: Zuul
Branch: master

commit 7377846f8a4e2f88f412018fb20c792b1abcea4a
Author: Marcin Juszkiewicz <email address hidden>
Date: Thu Dec 21 08:29:56 2017 +0000

    mariadb: enable galera clustering by default

    Kolla assumes mariadb 10.0 where galera stuff was always enabled. And
    this works for CentOS and Ubuntu as they use 10.0 on x86-64.

    Debian uses mariadb 10.1 by default (and CentOS on !x86-64 and
    Ubuntu/aarch64) where galera stuff is disabled by default.

    Closes-Bug: 1740060
    Co-Authored-By: Xinliang Liu <email address hidden>
    Change-Id: I8374ac2219ad7880970cd789727d01af7cac1077

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/529199
Committed: https://git.openstack.org/cgit/openstack/kolla/commit/?id=6ff3a55aedf69173d6a1ef5008072273fb698edf
Submitter: Zuul
Branch: master

commit 6ff3a55aedf69173d6a1ef5008072273fb698edf
Author: Xinliang Liu <email address hidden>
Date: Wed Dec 20 10:11:10 2017 +0800

    Fix MariaDB bootstrap for 10.1 version

    Option "wsrep_on" behaves differently between 10.0 and 10.1 [1]:
    "Before MariaDB 10.1, even though this variable is ON by default,
    its value get automatically adjusted based on whether mandatory
    configurations to turn on Galera replication have been specified.
    Since MariaDB 10.1, it is set to OFF by default and must be turned
    on to enable Galera replication."

    So on MariaDB 10.0 although wsrep_on set to OFF, its value will
    automatically adjusted to ON because wsrep mandatory configurations
    are set. Whereas on MariaDB 10.1, it will failed at galera provider
    'wsrep_ready' checking because wsrep_on is set to OFF.

    We can set wsrep_on to ON to handle both 10.0 and 10.1.

    But, the point is that the cluster bits, which are creating a cluster
    and wsrep_ready checking, are no need at bootstrap stage.

    At bootstrap stage it mainly do two things:
    Creating required system DBs (by mysql_install_db)
    and securing the mariadb (by bootstrap_db).

    After the bootstrap stage, it will create a cluster when starting the
    first node.

    [1] https://mariadb.com/kb/en/library/galera-cluster-status-variables/#wsrep_ready

    Partial-Bug: 1740060
    Co-Authored-By: Steven Dake <email address hidden>
    Change-Id: Ia2acb09e877a586243fc1acb49d8d140cf27d7b5

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/kolla-ansible 6.0.0.0b3 development milestone.