Adding checks to ensure historical tiers also undergo rollingDeploy and do not deploy in parallel #347
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Description
In the current Druid Operator, when rollingDeploy is enabled, the expectation is that the nodes will restart one at a time in the pre-defined order. In the case where we have multiple tiers within historicals, that is equivalent to having multiple Stateful Sets of NodeType historical. The Operator then does not stop to check whether each historical tier Statefulset is deployed and ends up deploying all historical tiers one after the other without waiting for a full deployment of the previous StatefulSet.
This PR aims to solve this issue by introducing a check on all historical tiers present in that cluster, if rollingDeploy is enabled, before going ahead with the next tier's deployment. In the specific case when we have replicas of datasource distributed across multiple tiers, we do not want all the tiers going down simultaneously (with rollingDeploy enabled), which might result in none of the segments being available, and hence downtime. This PR would solve that.
This PR has:
Key changed/added files in this PR
MyFoo
OurBar
TheirBaz