HDDS-15889. Show failed MoveResult breakdown in ozone admin containerbalancer status -v

[sreejasahithi]

What changes were proposed in this pull request?

Improves observability of Container Balancer move failures in ozone admin containerbalancer status -v.

Previously, verbose status only showed aggregate counts (“Failed to move containers”, “Failed to move containers by timeout”) with no breakdown of why moves failed, so users had to dig through SCM logs.

This change tracks per-iteration move failures on the SCM side and surfaces them in the CLI:

• Failure breakdown — counts grouped by reason (e.g. REPLICATION_FAIL_TIME_OUT, PRE_MOVE_CONTAINER_NOT_FOUND, ITERATION_MOVE_TIMEOUT, plus other MoveResult values)
• Failed move details — sample failed moves with container ID and source/target datanode UUIDs (capped at 100 total, 10 per reason; counts are not capped)

What is the link to the Apache JIRA

HDDS-15889

How was this patch tested?

Added test cases.
Tested in docker ozone-balancer cluster:

bash-5.1$ ozone admin containerbalancer start \
  -t 0.1 -d 100 -i 2 \
  --move-replication-timeout-minutes 1 \
  --move-timeout-minutes 16 \
  --balancing-iteration-interval-minutes 1
Container Balancer started successfully.
bash-5.1$

bash-5.1$ ozone admin containerbalancer status --verbose --history
ContainerBalancer is Running.
Started at: 2026-08-03 05:04:17
Balancing duration: 5m 49s

Container Balancer Configuration values:
Key                                                Value
Threshold                                          0.1
Max Datanodes to Involve per Iteration(percent)    100
Max Size to Move per Iteration                     500GB
Max Size Entering Target per Iteration             26GB
Max Size Leaving Source per Iteration              26GB
Number of Iterations                               2
Time Limit for Single Container's Movement         16min
Time Limit for Single Container's Replication      1min
Interval between each Iteration                    1min
Whether to Enable Network Topology                 false
Whether to Trigger Refresh Datanode Usage Info     false
Container IDs to Include in Balancing              None
Container IDs to Exclude from Balancing            None
Datanodes Specified to be Balanced                 None
Datanodes Excluded from Balancing                  None

Current iteration info:
Key                                                Value
Iteration number                                   2
Iteration duration                                 1m 15s
Iteration result                                   -
Size scheduled to move                             300 MB
Moved data size                                    0 B
Scheduled to move containers                       3
Already moved containers                           0
Failed to move containers                          0
Failed to move containers by timeout               0
Entered data to nodes
750e0c27-4d66-4e98-96e2-62a6d4351b52 <- 100 MB
df26a64a-da07-4207-8310-f6aa427c9e8d <- 100 MB
9d674491-0530-438c-90a5-7f7c833edc86 <- 100 MB
Exited data from nodes
8768b1cf-8397-4f31-883f-3222e7abde05 -> 100 MB
700868a5-6c48-4139-949e-58697d21a14e -> 100 MB
86f4d3f6-7da3-4a41-8b2e-f582519d30fd -> 100 MB

Completed iteration history:
Key                                                Value
Iteration number                                   1
Iteration duration                                 3m 34s
Iteration result                                   ITERATION_COMPLETED
Size scheduled to move                             300 MB
Moved data size                                    0 B
Scheduled to move containers                       3
Already moved containers                           0
Failed to move containers                          0
Failed to move containers by timeout               3
Failure breakdown
  REPLICATION_FAIL_TIME_OUT                        3
Failed move details
  REPLICATION_FAIL_TIME_OUT
    container 1  source 700868a5-6c48-4139-949e-58697d21a14e  target 750e0c27-4d66-4e98-96e2-62a6d4351b52
    container 2  source 8768b1cf-8397-4f31-883f-3222e7abde05  target df26a64a-da07-4207-8310-f6aa427c9e8d
    container 3  source 86f4d3f6-7da3-4a41-8b2e-f582519d30fd  target 9d674491-0530-438c-90a5-7f7c833edc86
Entered data to nodes
750e0c27-4d66-4e98-96e2-62a6d4351b52 <- 100 MB
df26a64a-da07-4207-8310-f6aa427c9e8d <- 100 MB
9d674491-0530-438c-90a5-7f7c833edc86 <- 100 MB
Exited data from nodes
8768b1cf-8397-4f31-883f-3222e7abde05 -> 100 MB
700868a5-6c48-4139-949e-58697d21a14e -> 100 MB
86f4d3f6-7da3-4a41-8b2e-f582519d30fd -> 100 MB


bash-5.1$

Green CI : https://github.com/sreejasahithi/ozone/actions/runs/30628368322

[sreejasahithi]

@ashishkumar50 could you please review this PR.

[ashishkumar50]

@sreejasahithi Thanks for working on this, Please update the patch wrt count instead of showing containerids. Here are the initial comments.

[ashishkumar50]

I think Failure breakdown and Failed move details should be merged. Also instead of showing containerids, we should show count of failures for source and target, otherwise it will be too verbose. Issue generally happens at DN level(like slow/unhealthy etc), so count is enough to know which dn is problematic.

[ashishkumar50]

The proto already sorts failure summaries, then the CLI sorts them again which is not required. Remove from server side sort.

[ashishkumar50]

Please update as per dn count suggestion and remove these limits.

[ashishkumar50]

Use enum FailureReason instead of plain string.

[ashishkumar50]

Source or target can be null.