This knowledge base article provides steps of one \napproach approach which may resolve a "Database Not Responding" (DNR) message\nin messagein the Global Scan.
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When a DNR message appears on the Global Scan page,\ncheck check the uptime.log file for messages similar to the following line (numbers \nwill will likely be different from example):
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011-03-29 11:40:48,873 ERROR (ProtocolHandler:79) -\nIn In command entities=168,169,171,175,176,177,179|commandType=query|commandQueryName=GET_GLOBAL_SCAN_ENTITIES
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This type of message likely indicates that the\nGlobal theGlobal Scan page is attempting to display recent performance data from an \nelement element that has been removed or deleted from up.time. To verify this condition, run the following \nqueries queries to see if there are entries in the entity_latest_data_sample table that\ndo thatdo not correspond to an existing element in the entity table:
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select host_id from entity_latest_data_sample where\nhostwherehost_id not in (select entity_id from entity);
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For each ID that is listed from the above query,\nrun run the following two queries (replace <ID> with the ID number). The first query should return an empty set \nbut but the second should have one or more results.
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select entity_id from entity where entity_id =\n<ID><ID>;
select * from entity_latest_data_sample where host_id = <ID>;
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To remove the erroneous performance data that is\ncausing iscausing this issue, run the following delete statement.
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delete from entity_latest_data_sample where host_id\n= <ID>;
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Once the delete statement has been run for each of the ID's from the first query, view the GlobalScan page \nto to verify that the issue has been resolved.