HDDS-14498. Zero Downtime Upgrade Design (ZDU)#9664
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sodonnel wants to merge 14 commits intoapache:masterfrom
Open
HDDS-14498. Zero Downtime Upgrade Design (ZDU)#9664sodonnel wants to merge 14 commits intoapache:masterfrom
sodonnel wants to merge 14 commits intoapache:masterfrom
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jojochuang
reviewed
Jan 28, 2026
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| jira: HDDS-3331 | |||
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My local hugo failed to start until I added the date tag.
Suggested change
| jira: HDDS-3331 | |
| jira: HDDS-3331 | |
| date: 2026-01-23 |
And looks like it also needs these two
Suggested change
| jira: HDDS-3331 | |
| title: Zero Downtime Upgrade (ZDU) | |
| summary: New and improved framework to allow rolling upgrade without cluster downtime. |
ptlrs
reviewed
Jan 29, 2026
Comment on lines
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| 6. The finalize command is sent to SCM by the admin - this is what is used to switch the cluster to act as the new version. Upon receipt of the finalize command: | ||
| 7. SCM will finalize itself over Ratis, saving the new finalized version. | ||
| 8. It will notify datanodes over the heartbeat to finalize. | ||
| 9. After all healthy datanodes have been finalized, OM can be finalized. To do this, OM will have been polling SCM periodically to see if it should finalize. Only after SCM and all datanodes have been finalized will OM get a “ready to finalize” response from the poll. The OM leader will then send a finalize command over Ratis to all OMs. | ||
| 10. As OM is the entry point to the cluster for external clients, finalizing OM unlocks any new features in the upgraded version. |
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These don't render correctly
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What changes were proposed in this pull request?
This is a design document for Ozone Zero Downtime Upgrade (ZDU).
What is the link to the Apache JIRA
https://issues.apache.org/jira/browse/HDDS-14498
How was this patch tested?
N/A