Neo4j 远程访问问题

Question

I'm encountering issues regarding a new installation of Neo4j on Ubuntu 12.04; the server starts fine, without any major errors listed (start-up text posted below), but I cannot access the webadmin remotely, even with the line "org.neo4j.server.webserver.address=0.0.0.0" uncommented. Chrome simply times out (error message "Oops! Google Chrome could not connect to twofish.cs.unc.edu:7474") when I attempt to connect. There have been a couple other questions on SO that listed similar issues, but the solutions have just been "it fixed itself at some point."

So far, I've tried:

- uncommenting and recommenting that line in the server config file, with stopping and starting the server in between each change.
- restarting the entire Ubuntu server.

The start-up message for Neo4j is as follows:

twofish(66)% sudo service neo4j-service start

WARNING: Max 1024 open files allowed, minimum of 40 000 recommended. See the Neo4j manual. 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

Starting Neo4j Server...WARNING: not changing user process [3505]... waiting for server to be ready.... OK.

http://localhost:7474/ is ready.

I've also put the entire config folder up in a folder on drive: https://drive.google.com/folderview?id=0Bx98DkxmHnEtLXloTDJwSUdyLTg&usp=sharing

Any suggestions on what may be causing the issue?

Update: Regarding firewall settings, I can't provide too much information because I'm not in charge of security for it. The machine is part of a university's CS department network and I'm fairly sure firewall settings are managed at the network level, by someone above my pay grade. We do we have an instance of Neo4j running (and accessible remotely) on another server within the department; however, I don't know whether its firewall configurations (or what firewall software the department is even using) is the same as the server I'm having issues with.

Regarding connecting through localhost: I'm able to access the database with the neo4j-shell and running "curl http://localhost:7474" returns

{
  "management" : "http://localhost:7474/db/manage/",
  "data" : "http://localhost:7474/db/data/"
}t

I don't know if that means its accessible on the local machine or not though; I assume if curl isn't throwing an error, it is accessible from localhost...

Update: curl http://twofish.cs.unc.edu:7474 from a remote host returns curl: (7) couldn't connect to host , so apparently I can access through localhost, but not through a remote host.

Answer 1

Change the 7474 port in the Neo4j server configuration to port 80. Your university firewall most likely has blocked anything that is not on a pre-approved list of ports.

According to your curl request, the Neo4j server is running and available. The problem is in the network configuration.

Answer 2

Same issue here with neo4j 2.1.7. I followed these installation steps . In my case there are no firewall rules, also changed org.neo4j.server.webserver.address to 0.0.0.0 but still no luck, can connect from localhost but not from remote.

I found that the issue only verifies starting neo with:

service neo4j-service start

Instead everything is OK with this:

cd $NEO4J_HOME && ./neo4j start

I guess it's a bug in service scripts. Btw, the docs also states that

This approach to running Neo4j as a server is deprecated. We strongly advise you to run Neo4j from a package where feasible.

To make the story short, considered that in my case is not convenient to use packages, I've been able to solve the issue with:

1. ./bin/neo4j-installer install
2. update-rc.d -f neo4j-service remove
3. install and configure supervisord to manage neo service in place of System V startup links

If possible, installing neo4j using os package is preferred.

Answer 3

I know it's late but I'm just posting it if someone encounters this in the future. The problem comes from iptables usually, just disable it completely or (better) add the appropriate rule (before deny all) and that's it :)