Overwrite single value with hiera

[linuxmail]

hi,

I'm new to Hiera and I want to have the most parts as a classical manifest (profile::mysql::maxscale). but want to overwrite some lines, for example "password/user" or "servers" ...

Is that possible?

I tried the following:

maxscale::services_conf:
  default:
    config:
      Galera Monitor:
        user: 'foorbar'
        password: 'topsecret12354#'
        server: 'mariadb3.foo.example.com'

But it seems to be ignored. If it doesn't work, I expect, that I have to change the fixed name in the manifest, with variables. Right?

cu denny

[aerostitch]

Hi @linuxmail ,

Can you show me your profile::mysql::maxscale profile please?
What do you mean by "doesn't work"? What does the generated /etc/maxscale.conf file on the server look like vs expected?
Your hiera config looks correct. It's missing the rest of the Galera Monitor service config I guess.

Thanks
Joseph

[linuxmail]

hi @aerostitch

that is our config profile and it works so far so good. But on one or two servers I want a slightly different configuration, for example the password hash, or user/server ..

With my knowledge, I would change the hardcoded lines with variables, getting from hiera, maybe with defaults e.g.

$maxscale_servers = hiera('maxscale::servers', 'mariadb1,mariadb2')

# profile::mysql::maxscale
# modules/profile/manifests/mysql/maxscale.pp
class profile::mysql::maxscale {
  class { '::maxscale':
    install_repository => false,
    repo_custom_url    => 'http://foo.bar/debian/',
    repo_fingerprint   =>  '56045F842...CBFA4C0',
    services_conf      => {
      'default'        => {
        ensure         => 'running',
        logdir         => '/var/log/maxscale',
        datadir        => '/var/lib/maxscale/data',
        piddir         => '/var/run/maxscale',
        svcuser        => 'maxscale',
        svcgroup       => 'maxscale',
        errmsgsys_path => '/var/lib/maxscale',
        configfile     => '/etc/maxscale.cnf',
        'config'       => {
          'maxscale'   => {
            'threads'  => 2
          },
          'Galera Monitor'   => {
            'type'           => 'monitor',
            'module'          => 'galeramon',
            'user'           => 'maxscale',
            'passwd'         => '<secrethash>',
            'servers'       => 'mariadb1,mariadb2',
            'monitor_interval' => '1000',
            'disable_master_failback' => true,
            'detect_stale_master' => true,
            'use_priority' => true,
            'detect_replication_lag' => true,
          },
          'RW Split Router'   => {
            'type'            => 'service',
            'router'         => 'readwritesplit',
            'user'        => 'maxscale',
            'servers' => 'maria1db,mariadb2',
            'passwd'        => '<secrethash>',
            'max_slave_connections' => '100%',
            'localhost_match_wildcard_host' => '1',
            'enable_root_user' => '1',
            'router_options' => 'slave_selection_criteria=LEAST_GLOBAL_CONNECTIONS',
          },
          'Debug Interface'   => {
            'type'            => 'service',
            'router'          => 'debugcli',
          },
          'CLI'      => {
            'type'   => 'service',
            'router' => 'cli',
          },
          'Debug Listener'   => {
            'type'           => 'listener',
            'service'        => 'Debug Interface',
            'protocol'       => 'telnetd',
            'address'        => '127.0.0.1',
            'port'           => 4442,
          },
          'CLI Listener'   => {
            'type'         => 'listener',
            'service'      => 'CLI',
            'protocol'     => 'maxscaled',
            'port'         => 6603,
          },
          'ina-mariadb1'   => {
            'type'         => 'server',
            'address'      => '192.168.1.51',
            'protocol'     => 'MySQLBackend',
            'port'         => 3306,
          },
          'ina-mariadb2'   => {
            'type'         => 'server',
            'address'      => '192.168.1.50',
            'protocol'     => 'MySQLBackend',
            'port'         => 3306,
          },
        },
      },
    },
  }
}

cu denny

[aerostitch]

We actually don't deep merge the default config with the configuration provided so you would need to declare the entire config inside your hash (can be done in hiera).
What I personally would do is have the following in your profile:

class profile::mysql::maxscale {
  include '::maxscale'
}

And have in hiera the config that would look like (You could have, for example maxscale::install_repository, maxscale::repo_custom_url and maxscale::repo_fingerprint inside your common.yaml to be applied to all your configs by default):

maxscale::repo_custom_url: 'http://foo.bar/debian/'
maxscale::repo_fingerprint: '56045F842...CBFA4C0'
maxscale::services_conf:
  'default':
    datadir: '/var/lib/maxscale/data'
    config:
      maxscale:
        threads: 2
      'Galera Monitor':  
        type: 'monitor'
        module: 'galeramon'
        user: 'maxscale'
        passwd: '<secrethash>'
        servers: 'mariadb1,mariadb2'
        monitor_interval: 1000
        disable_master_failback: true
        detect_stale_master: true
        use_priority: true
        detect_replication_lag: true
      'RW Split Router':
        type: 'service'
        router: 'readwritesplit'
        user: 'maxscale'
        servers: 'maria1db,mariadb2'
        passwd: '<secrethash>'
        max_slave_connections: '100%'
        localhost_match_wildcard_host: 1
        enable_root_user: 1
        router_options: 'slave_selection_criteria=LEAST_GLOBAL_CONNECTIONS'
      'Debug Interface':
        type: 'service'
        router: 'debugcli'
      'CLI':
        type: 'service'
        router: 'cli'
      'Debug Listener':
        type: 'listener'
        service: 'Debug Interface'
        protocol: 'telnetd'
        address: '127.0.0.1'
        port: 4442
      'CLI Listener':
        type: 'listener'
        service: 'CLI'
        protocol: 'maxscaled'
        port: 6603
      'ina-mariadb1':
        type: 'server'
        address: '192.168.1.51'
        protocol: 'MySQLBackend'
        port: 3306
      'ina-mariadb2':
        type: 'server'
        address: '192.168.1.50'
        protocol: 'MySQLBackend'
        port: 3306

Note: the values that are already declared as the default in the define (https://github.com/tubemogul/puppet-maxscale/blob/master/manifests/instance.pp) don't need to be re-declared.
You can use the hiera example shown in the "Working with a single instance" paragraph of the readme as an example.

Does that makes sense?

Try to avoid hard-coded stuffs, it always ends up being a mess. ;)

[linuxmail]

hi @aerostitch

thanks for the example, but do I think right, that .. if we have 5 hosts, all with some slightly different configurations, I need the whole config (except the package defaults) ? Hmm, what I didn't say: I have the option ":merge_behavior: deeper" in hiera.yaml, so I thought, that it should work :-)
Maybe, I red something about - roles/%{calling_class_path} (in my case profile/{calling_class_path} so I can move the content from the node.yaml to profile and overwrite only what is needed.

Hhu .. so many new things :-)

Thanks for the help 👍