I have neo4j installed (& the conf file says that authentication is off.)
I start the movie demo --- and am told to connect to the server.
When I type
:server connect
with No Authentication
the browser tells me that there is a graph waiting for me but then gives the message "Unable to extract host form undefined."
If you simply want to run the movie demo, you might prefer to use the free Neo4j sandbox rather than Neo4j Desktop. It runs in a web browser and there is nothing to install.
https://sandbox.neo4j.com/
If you prefer to use Neo4j Desktop, confirm that your database has started.
https://www.markhneedham.com/blog/2018/03/20/neo4j-undefined-unable-to-extract-host-from-undefined/
Related
I created the 3 necessary containers for NuoDB using the NuoDB instructions.
My Docker environment runs on a virtual Ubuntu Linux environment (VMware).
Afterwards I tried to access the database using a console application (C# .Net Framework 4.8) and the Ado.Net technology. For this I used the Nuget "NuoDb.Data.Client" from Nuget.org.
Unfortunately the connection does not work.
If I choose port 8888, my thread disappears to infinity when I open the connection.
For this reason I tried to open the port 48004 to get to the admin container.
On this way I get an error message.
"System.IO.IOException: A connection attempt failed because the remote peer did not respond properly after a certain period of time, or the established connection was faulty because the connected host did not respond 172.18.0.4:48006, 172.18.0.4"
Interestingly, if I specify a wrong database name, it throws an error:
No suitable transaction engine found for database.
This tells me that it connects to the admin container.
Does anyone have any idea what I am doing wrong?
The connection works when I establish a connection with the tool "dbvisualizer".
This tool accesses the transaction engine directly. For this reason I have opened the port 48006 in the corresponding container.
But even with these settings it does not work with my console application.
Thanks in advance.
Port 8888 is the REST port that you would use from the administration tool such as nuocmd: it allows you to start/stop engines and perform other administrative commands. You would not use this port for SQL clients (as you discovered). The correct port to use for SQL clients is 48004.
Port 48004 allows a SQL client to connect to a "load balancer" facility that will redirect it to one of the running TEs. It's not the case that the SQL traffic is routed through this load balancer: instead, the load balancer replies to the client with the address/port of one of the TEs then the client will disconnect from the load balancer and re-connect directly to the TE at that address/port. For this reason, all the ports that TEs are listening on must also be open to the client, not just 48004.
You did suggest you opened these ports but it's not clear from your post whether you followed all the instructions on the doc page you listed. In particular, were you able to connect to the database using the nuosql command line tool as described here? I strongly recommend that you ensure that simple access like this works correctly, before you attempt to try more sophisticated client access such as using Ado.Net.
Please I am trying to access the Neo4j database via its browser. I have used both bolt//:localhost:7687 and http//:localhost:7474, and Username: "neo4j" and Password:"neo4j" but with no success. I can't even start a database instance.
I have uninstalled and reinstalled Neo4j on my computer; I have updated Powershell on my Windows 8.1 computer, yet I keep getting an error message whenever I try to run the Movie database in the desktop.
I have also looked into the log.log file, but can't seem to find anything other than that I should update Powershell, which I have done.
I have corresponded with a relations officer at Neo4j, over 30 emails, and still I can't access Neo4j database.
Could it have anything to do with my web browser? I use Mozilla Firefox.
Because I am unable to successfully connect to Neo4j database, I can't call the api in R Studio and run cypher queries.
Does Neo4j have a web version, which I could use, since the desktop version isn't working?
Please does anybody have any idea or advice on what I could do to resolve this problem? I am really exasperated right now.
I have a successful import using the bin/neo4j-admin tool, can see the new database folder in my /databases, have restarted the server, but cannot get the database to appear in the console as an option to switch to. Do you have any suggestions for getting a newly imported database to be available in the console?
I assume that you are referring to the Neo4j Desktop environment.
The Desktop currently seems to be designed to support local DBs created by the Desktop itself.
As a workaround, you can:
Create a new "Graph" in the Desktop, using the "Connect to Remote Graph" option.
Accept the default "bolt://localhost:7687" as the Connect URL (assuming the default is acceptable).
Manually start your local neo4j installation from the command line, and
Click Connect on your "Graph" to connect.
Be aware that the Desktop has fewer bells and whistles for "remote
graphs".
I resolved the issue. The steps I found to successfully import a set of CSV using the admin -import tool is to:
Stop the server
Run the admin -import tool and use --database=aDatabaseName
Start the server
In the console switch to the System database using the pulldown control
Run the following command at the system prompt: create database aDatabaseName
(should be the same name set in #2 above)
Switch to the database just created using the console pulldown control
I was able to see the database nodes and relationships I created following the above steps
This is what worked for me. I was trying to access my database generated through neo4j-admin on my Neo4j Desktop app browser console.
On Neo4j Desktop App open the browser of the database server you want to include the new database
Switch to the system database https://neo4j.com/developer/manage-multiple-databases/
:use system
as system, create the database you want to import
:create database dbname
Stop the server
Use the neo4-admin tool to import the database https://neo4j.com/graphacademy/online-training/v4/19-using-neo4j-admin-tool-import/ (make sure to use the same name --database dbname). Run these command on the terminal opened from the Desktop app under the databases>_Open Terminal. On windows the neo4j-admin.bat is located in the bin directory
start the server and open the neo4j browser and switch to the system database https://neo4j.com/developer/manage-multiple-databases/
:use system
To list all the database available to use as system
:dbs
switch to your imported database
:use dbmame
Your browser console is ready now for your queries.
I am setting up window service for my neo4j database. I am able to start that from service and I can do a http post cypher query using localhost. However, I can't connect to the neo4j db remotely.
If I start the neo4j db via neo4j Desktop, I can perform http post both locally and remotely.
When I compared the neo4j logs generated using service start vs neo4j desktop start, they are quite different but no error on the service one.
Any idea?
By default, Neo4j server is not accessible remotely.
You need to change $NEO4J_HOME/conf/neo4j.conf.
Find this line:
#dbms.connector.http.address=localhost:7474
And Replace it with:
dbms.connector.http.address=0.0.0.0:7474
Setting connector address to 0.0.0.0 makes it accessible remotely.
I installed Neo4j 3.2.6 on Ubuntu 16.04 and I tried to access it remotely using putty (from my windows-based computers). Without uncommenting anything in neo4j.conf, I can access Neo4j using the source port I defined in putty. Then, after connecting with the initial password "Neo4j" in the section saying "Connect to Neo4j Database access requires an authenticated connection.", I gets the famous error "ServiceUnavailable: WebSocket connection failure. Due to security constraints in your web browser, the reason for the failure is not available to this Neo4j Driver. Please use your browsers development console to determine ...".
So, after googling, I uncommented:
dbms.connectors.default_listen_address=0.0.0.0
dbms.connector.bolt.listen_address=:7687
BUT NOTHING WORKS.
The interesting thing is that I tried to install Neo4j on my laptop (locally) and it worked and when I used its "bolt://..." database access password on my remote access "bolt://..." database access it works.So, I'm not sure what is going on here, can someone help?