HBASE-30142 Resolve NPE while running recoverUnknown command because null RegionLocation#8192
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Umeshkumar9414 wants to merge 2 commits into
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HBASE-30142 Resolve NPE while running recoverUnknown command because null RegionLocation#8192Umeshkumar9414 wants to merge 2 commits into
Umeshkumar9414 wants to merge 2 commits into
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wchevreuil
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Makes sense. Should we add UT for this?
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@wchevreuil Added an test. Let me know if it looks good. |
mnpoonia
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May 12, 2026
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Pull request overview
Fixes HBASE-30142 by ensuring recoverUnknown/scheduleSCPsForUnknownServers does not treat regions with a null ServerName (i.e., null region location during transitions/failed-open handling) as “unknown servers,” avoiding spurious SCP scheduling and potential NPEs.
Changes:
- Update
ServerManager#isServerUnknownto returnfalsefornullserver names. - Add a new master-level mini-cluster test that drives a region into
ABNORMALLY_CLOSEDwith anulllocation and verifiesscheduleSCPsForUnknownServersschedules no SCPs.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
hbase-server/src/main/java/org/apache/hadoop/hbase/master/ServerManager.java |
Adjusts “unknown server” classification to ignore null server names and updates Javadoc. |
hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestRecoverUnknownWithNullRegionLocation.java |
Adds regression coverage for recoverUnknown when a region’s location is null but state is non-OFFLINE. |
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| * any more, for example, a very old previous instance). A null serverName should not be | ||
| * considered unknown. We set regionLocation null before finding the assign candidate (in-between | ||
| * region transition) or while marking it OFFLINE/FAILED_OPEN For more info regarding null-check | ||
| * in this refer HBASE-30142 |
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| assertTrue(node.isInState(RegionState.State.ABNORMALLY_CLOSED), | ||
| "regionClosedAbnormally must move state to ABNORMALLY_CLOSED"); | ||
| assertNull(node.getRegionLocation(), "regionClosedAbnormally must null out the location"); | ||
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| MasterProtos.ScheduleSCPsForUnknownServersResponse response = | ||
| master.getMasterRpcServices().scheduleSCPsForUnknownServers(null, | ||
| MasterProtos.ScheduleSCPsForUnknownServersRequest.newBuilder().build()); |
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This is a good suggestion.
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MasterRpcServices.scheduleSCPsForUnknownServers() has no null guard before calling isServerUnknown(). With the old code, regions with null serverName (OFFLINE/FAILED_OPEN in-between state) would spuriously trigger a ServerCrashProcedure. The fix prevents that.