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Diffstat (limited to 'puppet/services/README.rst')
| -rw-r--r-- | puppet/services/README.rst | 32 |
1 files changed, 29 insertions, 3 deletions
diff --git a/puppet/services/README.rst b/puppet/services/README.rst index 6e4e9c1d..9c2d8c5c 100644 --- a/puppet/services/README.rst +++ b/puppet/services/README.rst @@ -49,6 +49,32 @@ are re-asserted when applying latter ones. 5) Service activation (Pacemaker) +Batch Upgrade Steps +------------------- + +Each service template may optionally define a `upgrade_batch_tasks` key, which +is a list of ansible tasks to be performed during the upgrade process. + +Similar to the step_config, we allow a series of steps for the per-service +upgrade sequence, defined as ansible tasks with a tag e.g "step1" for the first +step, "step2" for the second, etc (currently only two steps are supported, but +more may be added when required as additional services get converted to batched +upgrades). + +Note that each step is performed in batches, then we move on to the next step +which is also performed in batches (we don't perform all steps on one node, +then move on to the next one which means you can sequence rolling upgrades of +dependent services via the step value). + +The tasks performed at each step is service specific, but note that all batch +upgrade steps are performed before the `upgrade_tasks` described below. This +means that all services that support rolling upgrades can be upgraded without +downtime during `upgrade_batch_tasks`, then any remaining services are stopped +and upgraded during `upgrade_tasks` + +The default batch size is 1, but this can be overridden for each role via the +`upgrade_batch_size` option in roles_data.yaml + Upgrade Steps ------------- @@ -71,9 +97,9 @@ step, "step2" for the second, etc. 5) Perform any migration tasks, e.g DB sync commands - 6) Start control-plane services - - 7) Any additional online migration tasks (e.g data migrations) +Note that the services are not started in the upgrade tasks - we instead re-run +puppet which does any reconfiguration required for the new version, then starts +the services. Nova Server Metadata Settings ----------------------------- |