Installing Neo4j Community Server V4.0.1 on macOS - neo4j

Can I have two versions of the Neo4j Community Server database (V3.5 and V4.0.1) installed in macOS? I'd like to continue working with the V3.5 database for my current project, begin testing V4.0.1, migrate the current database to V4.0.1, and use V4.0.1 for my new project. Has anyone tried this?

Perhaps a good strategy would be to use separate Docker containers.
If you want to use the same data set, you might try grabbing the Neo4j 3.5 container from Docker Hub and following the migration path (https://neo4j.com/docs/operations-manual/current/upgrade/) to test out the actual migration and continue working with your data from 3.
You could also, of course, grab the Neo4j 4.0 container from Docker Hub and start playing around with new data if you just want to test out features.

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Move Neo4j databases in Neo4j Desktop from one computer to another

I am upgrading my local machine from Ubuntu 16.04 to 20.04. I run Neo4j Desktop (version 1.2.7) on my 16.04 and have installed it on the 20.04 machine and want to move the databases over.
I'm sure that in the past I just copied and pasted the database folders in /home/dougi/.config/Neo4j Desktop/Application/neo4jDatabases from one computer to the other and started Neo4j Desktop. However, when I do that no database show in the project.
I tried doing a dump and load, but couldn't see how I would load the database into Neo4j Desktop on the 20.04 machine as you have to "create" a database for it to show in the project and the database version when creating is limited to 4.0.3 and all of my databases are earlier versions than that (I don't want upgrade them right now).
I tried creating a database, deleting the files in the folder created in /home/dougi/.config/Neo4j Desktop/Application/neo4jDatabases and pasting the database folder from the 16.04 machine into it (i.e. replacing the files it created). I just get a message saying that the database files have been moved or corrupted when I load Neo4j Desktop.
I tried running a load from a dump I had made and had an error saying WARNING: Max 1024 open files allowed, minimum of 40 000 recommended.. I did find some google articles on that, but this felt like a really messy way of doing the restore so I didn't go any further with that.
What is the easiest way to move Neo4j Desktop databases from one computer to another please?
Thank you!
OK, so the answer to this is that there is a file /home/dougi/.config/Neo4j Desktop/Application/persist/databases.json which contains the list of databases that display in Neo4j Desktop.
Create a new database to add an entry to the file and then copy and paste that entry, replacing the database ID and version with those of the new databases you are adding files for to create an entry for each of the databases.
Restart your computer and delete the temporary database you created.
Or you could just copy the file from your previous version of Neo4j Desktop, assuming there are no formatting changes between versions of Neo4j Desktop.

Copy Neo4j Desktop Edition DB to cloud

I am trying to get the Paradise Papers running on an AWS cloud server. I installed Neo4j Desktop on my mac, and commissioned a server by deploying the AMI from https://aws.amazon.com/marketplace/pp/B071P26C9D.
I then copied the data from the Desktop install to the cloud install, updated the neo4j.template file to point to the new directory, and restarted the service.
The problem is that I can no longer connect to the server. In the log files I can see the following lines (along with a lot of diagnostic information).
2018-09-30 07:41:59.920+0000 INFO [o.n.k.i.f.CommunityEditionModule] No locking implementation specified, defaulting to 'community'
2018-09-30 07:42:00.104+0000 INFO [o.n.k.AvailabilityGuard] Requirement makes database unavailable: Database available
I suspect that there may be some kind of licensing or version constraint that is preventing the database from running. Could this be possible? Or is it something else?
Your issue is not related with a licensing or version problem.
In your debug.log, I don't see any message that can explained your issue.
Is there something useful in the neo4j.log file ?
Can you try to start neo4j after after removing all your plugins (apoc) ?
Can you try to start Neo4j on an empty database ?
Cheers

Neo4j community edition in read-only mode

I'm trying to make the config flag dbms.read_only=true working with Neo4j community edition (I know there are user roles in the enterprise, but I'm not wealthy enough for their expensive fees).
I've done this:
Created a database as read/write, using Neo4j Desktop (v1.1.8) under Mac and 3.4.5 as database engine.
Populated it with just a few nodes
Stopped, set dbms.read_only=true and restarted
At the last step, the server logs shows the error: "UnsupportedOperationException: Can't create index writer in read only mode" and shuts down. So, is that option really (still) working?
Neo4j Desktop is meant for usage with Enterprise Edition (you do get an individual license for usage for dev purposes only), not Community Edition.
I believe there's an issue with dbms.read_only=true and running via Neo4j Desktop, but there isn't any problem using the server deployment of Neo4j Community edition and using that setting.
My advice would be to download the community edition from Neo4j and use that directly rather than going through Neo4j Desktop.

Unable to connect to Neo4j db using gremlin - Error instantiating Neo4j Database

I am new to the neo4j-gremlin. I have downloaded the latest version of tinkerpop-3.3.1 and neo4j-community-3.3.3 on Windows machine.
I followed the installation instructions given on the tinkerpop site for Neo4j-Gremlin and was able to install neo4j-gremlin plugin but when i try to connect to the neo4j graph.db using gremlin console(graph = Neo4jGraph.open('C:/neo4j/data/databases/graph.db'))
I get the following error. Also the display stack trace option is also not available. It jumps directly to gremlin prompt. Any thoughts?
Error instantiating Neo4j Database for C:/neo4j/data/databases/graph.db
I was able to bring this setup with gremlin-server running Neo4j plugin. You can look at my GitHub project https://github.com/achandak123/gremlin-orm-neo4j. Don't worry about the README version talking about 2.3 n all. This works with tinker pop 3.3.1 and neo4j plugin

Its lock file has been locked by another process - Neo4j Embedded

I am developing a embedded application of the Neo4j and I try run this but I get this error:
Store and its lock file has been locked by another process:
/home/dev/neo4j-community-2.3.2/data/graph.db/store_lock. Please
ensure no other process is using this database, and that the directory
is writable (required even for read-only access)
I know that is because the neo4j server application is running and it lock the directory to writable for another application.
But I want run both, the neo4j server with browser studio and my embedded application.
I am use the community edition 2.3.2 in Linux.
How can I do it?
It is possible in enterprise version?
Thanks
On the very same directory you can only run at most one instance at a given time.
Enterprise edition enables master-slave replication, so the graph.db is folder is propagated from master to slave instance. This would be an option for you.
I assume you want to access you embedded instance via the browser. See this blog post http://graphaware.com/neo4j/2014/11/21/neo4j-browser-with-embedded.html - be aware this one is based on 2.1 - as far as I remember in 2.3 some things have changed since then.

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