修复损坏的neo4j数据库（2.3.2社区）

Question

我的 neo4j-2.3.2-community 数据库磁盘空间不足（80G）。我彻底关闭了它，然后添加了更多磁盘，并尝试重新启动它，只是得到了神秘的错误消息并让它拒绝启动。

今天早上，当我意识到磁盘已满并且不再接受任何插入时，我将其关闭。直到今天晚上，我才开始尝试恢复它。对于关闭和重新启动之间日志中的明显差距，我深表歉意。该数据库仍处于原型/概念验证阶段。在过去一周左右的时间里，我一直在运行作业以在其中加载数据。我真的，真的不想从那个数据加载过程重新开始。实在是太慢了。

我希望有人会告诉我有一个“neo4j --force_repair”类型的命令行选项可以解决问题。我的数据加载器足够智能，可以在尝试加载新记录之前检查它成功插入数据库的最后一条记录，所以如果我们丢失了一些记录应该没问题。

这是我在 console.log 中看到的内容。

2016-01-31 16:25:56.648+0000 INFO  Successfully shutdown Neo4j Server
2016-01-31 16:25:56.810+0000 INFO  Successfully stopped database
2016-01-31 16:25:56.811+0000 INFO  Successfully shutdown database
2016-02-01 01:16:10.591+0000 INFO  Successfully shutdown Neo4j Server
2016-02-01 01:16:10.593+0000 ERROR Failed to start Neo4j: Starting Neo4j failed: Component 'org.neo4j.server.database.LifecycleManagingDatabase@2d9e9010' was successfully initialized, but failed to start. Please see attached cause exception. Starting Neo4j failed: Component 'org.neo4j.server.database.LifecycleManagingDatabase@2d9e9010' was successfully initialized, but failed to start. Please see attached cause exception.
org.neo4j.server.ServerStartupException: Starting Neo4j failed: Component 'org.neo4j.server.database.LifecycleManagingDatabase@2d9e9010' was successfully initialized, but failed to start. Please see attached cause exception.
    at org.neo4j.server.exception.ServerStartupErrors.translateToServerStartupError(ServerStartupErrors.java:67)
    at org.neo4j.server.AbstractNeoServer.start(AbstractNeoServer.java:234)
    at org.neo4j.server.Bootstrapper.start(Bootstrapper.java:97)
    at org.neo4j.server.CommunityBootstrapper.start(CommunityBootstrapper.java:48)
    at org.neo4j.server.CommunityBootstrapper.main(CommunityBootstrapper.java:35)
Caused by: org.neo4j.kernel.lifecycle.LifecycleException: Component 'org.neo4j.server.database.LifecycleManagingDatabase@2d9e9010' was successfully initialized, but failed to start. Please see attached cause exception.
    at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.start(LifeSupport.java:462)
    at org.neo4j.kernel.lifecycle.LifeSupport.start(LifeSupport.java:111)
    at org.neo4j.server.AbstractNeoServer.start(AbstractNeoServer.java:194)
    ... 3 more
Caused by: java.lang.RuntimeException: Error starting org.neo4j.kernel.impl.factory.CommunityFacadeFactory, /home/neo4j/neo4j-community-2.3.2/data/graph.db
    at org.neo4j.kernel.impl.factory.GraphDatabaseFacadeFactory.newFacade(GraphDatabaseFacadeFactory.java:143)
    at org.neo4j.kernel.impl.factory.CommunityFacadeFactory.newFacade(CommunityFacadeFactory.java:43)
    at org.neo4j.kernel.impl.factory.GraphDatabaseFacadeFactory.newFacade(GraphDatabaseFacadeFactory.java:108)
    at org.neo4j.server.CommunityNeoServer$1.newGraphDatabase(CommunityNeoServer.java:66)
    at org.neo4j.server.database.LifecycleManagingDatabase.start(LifecycleManagingDatabase.java:95)
    at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.start(LifeSupport.java:452)
    ... 5 more
Caused by: org.neo4j.kernel.lifecycle.LifecycleException: Component 'org.neo4j.kernel.recovery.Recovery@4ec23a22' failed to initialize. Please see attached cause exception.
    at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.init(LifeSupport.java:434)
    at org.neo4j.kernel.lifecycle.LifeSupport.init(LifeSupport.java:66)
    at org.neo4j.kernel.lifecycle.LifeSupport.start(LifeSupport.java:102)
    at org.neo4j.kernel.NeoStoreDataSource.start(NeoStoreDataSource.java:600)
    at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.start(LifeSupport.java:452)
    at org.neo4j.kernel.lifecycle.LifeSupport.start(LifeSupport.java:111)
    at org.neo4j.kernel.impl.transaction.state.DataSourceManager.start(DataSourceManager.java:112)
    at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.start(LifeSupport.java:452)
    at org.neo4j.kernel.lifecycle.LifeSupport.start(LifeSupport.java:111)
    at org.neo4j.kernel.impl.factory.GraphDatabaseFacadeFactory.newFacade(GraphDatabaseFacadeFactory.java:139)
    ... 10 more
Caused by: java.lang.IllegalArgumentException: Unknown entry type -1 for version -1. At position LogPosition{logVersion=252, byteOffset=100663356} and entry version V2_1
    at org.neo4j.kernel.impl.transaction.log.entry.LogEntryVersion.entryParser(LogEntryVersion.java:207)
    at org.neo4j.kernel.impl.transaction.log.entry.VersionAwareLogEntryReader.readLogEntry(VersionAwareLogEntryReader.java:92)
    at org.neo4j.kernel.impl.transaction.log.LogEntryCursor.next(LogEntryCursor.java:54)
    at org.neo4j.kernel.recovery.LatestCheckPointFinder.find(LatestCheckPointFinder.java:77)
    at org.neo4j.kernel.recovery.PositionToRecoverFrom.apply(PositionToRecoverFrom.java:53)
    at org.neo4j.kernel.recovery.DefaultRecoverySPI.getPositionToRecoverFrom(DefaultRecoverySPI.java:135)
    at org.neo4j.kernel.recovery.Recovery.init(Recovery.java:72)
    at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.init(LifeSupport.java:424)
    ... 19 more

Answer 1

看起来事务日志仅被部分写入。如果这是真的，那么数据存储本身就不太可能损坏。

警告：在对 data/graph.db 文件夹进行任何手动更改之前，请务必准备好备份副本。

在继续之前，请阅读以上段落。备份了吗？如果是，请尝试通过rm neostore.transaction.db.* 删除data/graph.db 中的事务日志文件。尝试启动 Neo4j。如果它仍然无法启动，请粘贴包含最新启动序列的data/graph.db/messages.log 的 sn-p - 这应该可以提供更多信息。