Comment 6 for bug 1848060

Reviewed: https://review.opendev.org/688856
Committed: https://git.openstack.org/cgit/openstack/puppet-tripleo/commit/?id=82e304a419698e1243765557b66ee2ebd83d03bc
Submitter: Zuul
Branch: stable/rocky

commit 82e304a419698e1243765557b66ee2ebd83d03bc
Author: Michele Baldessari <email address hidden>
Date: Mon Oct 14 19:19:51 2019 +0200

    Deep merge hiera keys for mysqld_options

    Currently when adding some tuning options via hiera, galera won't start because
    overriding even a single mysql option will reset the whole key in the hash. So
    for example, when adding:
        tripleo::profile::base::database::mysql::mysql_server_options:
          mysqld:
            # MySQL InnoDB equally divided in 1GB instances
            innodb_buffer_pool_instances: 2
            # Query network write timeout raised to 120 seconds
            net_write_timeout: 120
            # Query network read timeout raised to 120 seconds
            net_read_timeout: 120
            # MySQL connection timeout set to 8 hours
            connect_timeout: 28800

    Things will break because all the wsrep options that are set normally will be
    overridden and galera will refuse to start

    Tested by passing the above hiera keys and observing the deploy complete
    successfully and the settings correctly applied to galera/mysql on the overcloud.

    Change-Id: I30f03bc8eb81db0243c137d4af08924adeebc951
    Closes-Bug: #1848060
    (cherry picked from commit 7e78ebdc0f3678afddea3bdab2007c7b6ac92776)
    (cherry picked from commit d12fe87318264c9423e6bc0ac509fa2978261f1c)