我一直在尝试在EC2实例上添加新数据后重新启动neo4j。我停止了neo4j实例，然后调用了systemctl start neo4j，但是当我调用cypher-shell时却说了Connection refused，并且与浏览器端口的连接不再起作用。
一开始我以为是堆空间问题，因为查看debug.log时说存在内存问题。我按照neo4j.conf的建议调整了neo4j-admin memrec中的堆空间和缓存设置，但neo4j仍然无法启动。
然后我认为这是因为我的APOC软件包已过时。我的neo4j版本是3.5.6，但是APOC是3.5.0.3。我下载了最新的3.5.0.4版本，但neo4j仍然无法启动。
最后，我在chmod 777和data/database目录中的每个文件以及目录本身上尝试了plugin，但是neo4j仍然无法启动。
奇怪的是，当我尝试neo4j console进行所有这些尝试时，cypher-shell和neo4j浏览器端口都可以正常工作。但是，显然，我希望能够使用systemctl启动neo4j。
现在，我在debug.log中发现的唯一错误提示如下：
2019-06-19 21:19:55.508+0000 INFO [o.n.i.d.DiagnosticsManager] Storage summary:
2019-06-19 21:19:55.508+0000 INFO [o.n.i.d.DiagnosticsManager] Total size of store: 3.07 GB
2019-06-19 21:19:55.509+0000 INFO [o.n.i.d.DiagnosticsManager] Total size of mapped files: 3.07 GB
2019-06-19 21:19:55.509+0000 INFO [o.n.i.d.DiagnosticsManager] --- STARTED diagnostics for KernelDiagnostics:StoreFiles
END ---
2019-06-19 21:19:55.509+0000 INFO [o.n.k.a.DatabaseAvailabilityGuard] Fulfilling of requirement 'Database available' mak
es database available.
2019-06-19 21:19:55.509+0000 INFO [o.n.k.a.DatabaseAvailabilityGuard] Database is ready.
2019-06-19 21:19:55.568+0000 INFO [o.n.k.i.DatabaseHealth] Database health set to OK
2019-06-19 21:19:56.198+0000 WARN [o.n.k.i.p.Procedures] Failed to load `apoc.util.s3.S3URLConnection` from plugin jar `
/var/lib/neo4j/plugins/apoc-3.5.0.4-all.jar`: com/amazonaws/ClientConfiguration
2019-06-19 21:19:56.199+0000 WARN [o.n.k.i.p.Procedures] Failed to load `apoc.util.s3.S3Aws` from plugin jar `/var/lib/n
eo4j/plugins/apoc-3.5.0.4-all.jar`: com/amazonaws/auth/AWSCredentials
2019-06-19 21:19:56.200+0000 WARN [o.n.k.i.p.Procedures] Failed to load `apoc.util.s3.S3Aws$1` from plugin jar `/var/lib
/neo4j/plugins/apoc-3.5.0.4-all.jar`: com/amazonaws/services/s3/model/S3ObjectInputStream
2019-06-19 21:19:56.207+0000 WARN [o.n.k.i.p.Procedures] Failed to load `apoc.util.hdfs.HDFSUtils$1` from plugin jar `/v
ar/lib/neo4j/plugins/apoc-3.5.0.4-all.jar`: org/apache/hadoop/fs/FSDataInputStream
2019-06-19 21:19:56.208+0000 WARN [o.n.k.i.p.Procedures] Failed to load `apoc.util.hdfs.HDFSUtils` from plugin jar `/var
/lib/neo4j/plugins/apoc-3.5.0.4-all.jar`: org/apache/hadoop/fs/FSDataOutputStream
...
...
...
2019-06-19 21:20:00.678+0000 INFO [o.n.g.f.GraphDatabaseFacadeFactory] Shutting down database.
2019-06-19 21:20:00.679+0000 INFO [o.n.g.f.GraphDatabaseFacadeFactory] Shutdown started
2019-06-19 21:20:00.679+0000 INFO [o.n.k.a.DatabaseAvailabilityGuard] Database is unavailable.
2019-06-19 21:20:00.684+0000 INFO [o.n.k.i.t.l.c.CheckPointerImpl] Checkpoint triggered by "Database shutdown" @ txId: 1
checkpoint started...
2019-06-19 21:20:00.704+0000 INFO [o.n.k.i.t.l.c.CheckPointerImpl] Checkpoint triggered by "Database shutdown" @ txId: 1
checkpoint completed in 20ms
2019-06-19 21:20:00.705+0000 INFO [o.n.k.i.t.l.p.LogPruningImpl] No log version pruned, last checkpoint was made in vers
ion 0
2019-06-19 21:20:00.725+0000 INFO [o.n.i.d.DiagnosticsManager] --- STOPPING diagnostics START ---
2019-06-19 21:20:00.725+0000 INFO [o.n.i.d.DiagnosticsManager] --- STOPPING diagnostics END ---
2019-06-19 21:20:00.725+0000 INFO [o.n.g.f.GraphDatabaseFacadeFactory] Shutdown started
2019-06-19 21:20:05.875+0000 INFO [o.n.g.f.m.e.CommunityEditionModule] No locking implementation specified, defaulting
to 'community'
2019-06-19 21:20:06.080+0000 INFO [o.n.g.f.GraphDatabaseFacadeFactory] Creating database.
2019-06-19 21:20:06.154+0000 INFO [o.n.k.a.DatabaseAvailabilityGuard] Requirement `Database available` makes database unavailable.
2019-06-19 21:20:06.156+0000 INFO [o.n.k.a.DatabaseAvailabilityGuard] Database is unavailable.
2019-06-19 21:20:06.183+0000 INFO [o.n.i.d.DiagnosticsManager] --- INITIALIZED diagnostics START ---
我认为警告不是问题，因为它只是警告，而不是错误或异常。同样，数据库似乎只是自动关闭，然后重新启动，从而创建了无限循环。当我调用neo4j console时，不会发生此循环（所有警告仍存在于日志中）。我所有的端口都是默认端口。
任何线索为什么会这样？我以前在此实例上启动neo4j时从未遇到过此错误。
答案 0 :(得分：0)
如果它适用于neo4j console而不适用于systemctl，则应检查Neo4j文件夹的权限。
我很确定您有问题，并且systemctl不会以与您相同的用户身份运行Neo4j