Neo4j: server won't start - neo4j

I am trying to switch from Java embbeded Neo4j database to standalone server but cannot find a way to import my database.
Whatever I do, I am getting the error: `Starting Neo4j failed: Component 'org.neo4j.server.database.LifecycleManagingDatabase#2190bb62' was successfully initialized, but failed to start. Please see attached cause exception.'
The problem is that the log file doesn't show anything useful:
2017-04-12 12:25:34.919+0000 INFO [o.n.s.CommunityNeoServer] ======== Neo4j .1.3 ========
2017-04-12 12:25:35.071+0000 INFO [o.n.s.d.LifecycleManagingDatabase] Starting...
2017-04-12 12:25:35.608+0000 INFO [o.n.b.v.r.WorkerFactory] Bolt enabled on localhost:7687.
2017-04-12 12:25:35.722+0000 INFO [o.n.k.i.s.p.StoreMigrator] Starting upgrade of database
I have activated the dbms.directories.import=import option to import an existing database that was created in 2.x
What should I do? is there any way to have more verbose logs?
I tried using Neo4j version 2.x, but I still get the same error when trying to start the server.

Related

Neo4j: How to bring database back online

I was running a large delete query and got an out of memory error, so the DB shutdown automatically. I restarted it, but it is still showing as 'offline' in Neo4j desktop.
Here are the log entries from the restart:
2021-08-01 23:47:03.506+0000 INFO Starting...
2021-08-01 23:47:06.804+0000 INFO ======== Neo4j 4.2.1 ========
Exception in thread "neo4j.Scheduler-1" java.lang.OutOfMemoryError: Java heap space
WARNING: sun.reflect.Reflection.getCallerClass is not supported. This will impact performance.
2021-08-01 23:47:22.505+0000 INFO Sending metrics to CSV file at /Users/my_user/Library/Application Support/Neo4j Desktop/Application/relate-data/dbmss/dbms-########-####-####-####-##########/metrics
2021-08-01 23:47:22.524+0000 INFO Bolt enabled on localhost:7687.
2021-08-01 23:47:23.836+0000 INFO Remote interface available at http://localhost:7474/
2021-08-01 23:47:23.837+0000 INFO Started.
Similarly, when I attempt to connect from a browser it tells me that the Neo4j database is unavailable.
In the log I can see that there is a Java out of memory error. Why would this appear? Does Neo4j queue/cache incomplete queries? And how do I go about clearing it if I can't access the server?
The data is only test data, so I don't need to save it. I do need to understand if I can fix it, and how, since I am putting the product through its paces for a new project.

Cant see any graphs in Neo4j

I just installed the latest version of Neo4J on ubuntu 15.04 and on my application code I have provided the path for the database as the following :
GraphDatabaseService db = dbFactory.newEmbeddedDatabase("/home/aimad/Documents/Neo4j/default.graphdb");
When I type match(n) return n; on console of http://localhost:7474 I cant see any graph.
And I notice that the location of the database is : /home/aimad/neo4j-community-2.3.0/data/graph.db on the Neo4j plateform.
I also tried to change the location of the database in conf/neo4j-server.properties but I got this error message when I want to start neo4j :
Starting Neo4j Server...WARNING: not changing user process [3151]...
waiting for server to be ready... Failed to start within 120 seconds.
Neo4j Server may have failed to start, please check the logs.
How can I solve this problem ?
As #AllessandroNegro indicated, you cannot start a neo4j server on the same DB that is already opened by an embedded app.
If you want to visualize the DB used by your embedded app, this other question might be helpful.

Unable to start Neo4j Server(neo4j-community-2.2.3)

After Remote System forced shutdown. Unable to start Neo4j Server. (neo4j-community-2.2.3)
data/log/console.log now says
2015-10-30 06:42:21.689+0000 INFO [API] Setting startup timeout to: 120000ms based on 120000
2015-10-30 06:42:22.188+0000 INFO [API] Successfully shutdown Neo4j Server.
Updated Link to messages.log
On searching the internet, possible solutions were
Changing the startup time
and the permission related issue
which I don't think is the solution since the server was running fine before.
How to start the server now?

Neo4j server failed to start :( It was working fine but suddenly it throwed error while starting.

i just tried to access Neo4j through Gephi. After that when i tried to access Neo4j, it throw the following error. I'm using Neo4j 2.0.1.
Error:
Starting Neo4j Server failed: Error starting org.neo4j.kernel.EmbeddedGraphDatabase, C:\Users\Sakthi\Documents\Neo4j\default.graphdb
Make sure you don't have another Neo4j server running against the same folder
Make sure the user running gephi has read/write access to that folder
Look for the messages.log in that folder, and see if you can find any exceptions

launchctl start error: Bad file descriptor when trying to start NEO4J server

Yesterday neo4j was working as expected, and today it isn't. I'm getting the following error:
unknownc8e0eb17b72f% ./bin/neo4j status
Neo4j Server is not running
unknownc8e0eb17b72f% ./bin/neo4j start
Using additional JVM arguments: -server -XX:+DisableExplicitGC
Dorg.neo4j.server.properties=conf/neo4j-server.properties -
Djava.util.logging.config.file=conf/logging.properties -
Dlog4j.configuration=file:conf/log4j.properties -XX:+UseConcMarkSweepGC -
XX:+CMSClassUnloadingEnabled
Detected installation in launchd, starting it...
launchctl start error: Bad file descriptor
Running ./bin/neo4j console does not cause problems and I can see my graphs using the web tool on my localhost.
Perhaps related, I'm using jexp's batch-import tool to import my data and the labels aren't coming through.
I've tried restarting, deleting and redownloading, etc. I'm using the 2.0 RCI version of neo4j.
I saw the related questions from ~6 months ago but with the new 2.0 build and the fact that following the advice on that thread didn't work for me made me want to open a new question.
You have it installed as a service. See this answer for how to uninstall:
"launchctl start error: Bad file descriptor" when trying to start Neo4j server

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