Neo4j Server running problems on Linux - linux

I am using Neo4j 2.0.3 Community server by installing it on my linux system (by unzipping the tar.gz). I got this error while I tried to start the server
WARNING! You are using an unsupported Java runtime.
process [50690]... waiting for server to be ready.neo4j-community-2.0.3/bin/neo4j: line 147: lsof : command not found
.neo4j-community-2.0.3/bin/neo4j: line 147: lsof : command not found
.neo4j-community-2.0.3/bin/neo4j: line 147: lsof : command not found
. Failed to start within 120 seconds.
Neo4j Server may have failed to start, please check the logs.
I checked for the solution for this and came to know that /usr/sbin had to be added to the path. On doing so and restarting the server, I got the following message
Another server-process is running with [40903], cannot start a new one. Exiting.
However, when I run the command neo4j staus , it says
Neo4j Server is not running
Can anybody please help me with how should I get started with it?

This is very late, but might help others.
If it tells you this, and you check that process id with, for example, ps aux | grep 40903, and it's not neo4j, the problem might be that the port is being used.
By default neo4j uses 7474, but can change this on the neo4j folder /conf/neo4j-server.properties and that was my problem, I had set the port to '22' which was being used. SO make sure it is set to a port that is open and available.
Hope this helps.

You might want to examine the startup script.
Another server-process is running with [40903], cannot start a new one. Exiting.
indicates (me to) that there might be a pid file (or the script uses them) which was written and is checked before attempting to start a new instances. This the normal thing to do.

I think you need to kill the other process using kill
You can see this answer for how to kill the process:
https://unix.stackexchange.com/questions/8916/when-should-i-not-kill-9-a-process
Otherwise, restarting the operating system will also do the job. For me, I normally start neo4j in the console, as in ./neo4j console. This makes it easier to stop the process.

Related

Cannot kill NodeJS process that always keeps restarting

I started a node script inside WebStorm once. It is a VueJS application. It is running on localhost:5000. When I open it inside chrome, I can see that it first is not responding, and then it suddenly loads. That tells me that the process is always restarting and inside a loop.
When I run ps aux | grep node , I can see the process quickly changing the process ID. That confirms my observation. If I try to kill the process it tells me that there is no process with that ID because it restarted that quickly. The process also is starting when reboot the computer. I also completely uninstalled NodeJS from my computer, but strangely it is starting anyways. I'm on macOS and I don't know what I could try anymore.
ps aux | grep node output:
2959 0,0 0,0 4268464 740 s000 S+ 3:47pm 0:00.00 grep --color=auto --exclude-dir=.bzr --exclude-dir=CVS --exclude-dir=.git --exclude-dir=.hg --exclude-dir=.svn --exclude-dir=.idea --exclude-dir=.tox node
I don't have enough reputation to leave a comment on your question, so I'm writing here.
It seems like you're application somehow registered in the service which happened to me as well. Mine was CentOS7.
You can check if it's added into service and run automatically whenever the machine is on. The command is Linux ones, so I'm not sure whether it's gonna work on MacOS as well.
//check list
chkconfig --list
//turn off the automatic start
chkconfig [your application name] off
If changing service config by using above commands did not work, you can search for the Mac Service Script. I think service shell script are different. Again, my case was on CentOS7.
Hope it helps.

How to track down process that's running too long?

I have a VPS with firewall and security notices enabled. I keep getting emails like this:
Time: Wed Jun 19 19:01:54 2019 -0500
Account: user
Resource: Process Time
Exceeded: 7248 > 3600 (seconds)
Executable: /opt/cpanel/ea-php72/root/usr/sbin/php-fpm
Command Line: php-fpm: pool domain_com
PID: 16374 (Parent PID:9915)
Killed: No
So for some reason with this example I have a script that has apparently been running for 2+ hours non-stop. I don't have anything that should be doing that.
I'm getting notices like this quite often. How can I use this info to track down what specifically is causing this?
Any information would be greatly appreciated. Thanks!
You can track which the exact process with the process ID mentioned.
lsof -p 16374
The alert which you are getting is from the LDF which is installed as a part of CSF. I think its normal for cPanel with php_fpm to have the process php_fpm run this long.
You can add the php-fpm to csf.pignore file to stop this warning.
You can also refer the below cPanel fourm thread.
https://forums.cpanel.net/threads/lfd-excessive-resource-usage-normal-for-php-fpm.592583/
To get more information on processes, I would use the Htop tool. This is a great article for learning about how to manage processes using htop and ps
Lsof (List open files) will tell you more information about what files the process is using.
You can get htop and lsof with
sudo apt install htop lsof -y
This article indicates that :
That message comes from the third-party CSF/LFD application and indicates a PHP-FPM process was running longer than the maximum time configured for the CSF/LFD detection period. It shows the process was not killed, thus you should not have traffic loss.
So you might want to check the PHP-FPM error log for the account in-question to see if you notice any particular error messages. It's located at:
/home/$username/logs/domain_tld.php.error.log
It looks like your specific issue has not been resolved on that form. So, you might want to try strace. It handles watching system calls made by a given process including all read-write operations and os function calls. You can activate it on the command line before the program you want to track or attach to a running process by hitting s on a process selected in htop.

nodejs process keeps respawning

I can no longer access my node.js application. I see thee following behaviours.
1> netstat shows the server listening on the port I expect it to.
2> tcpdump shows traffic from my laptop on the server when I attempt to open the page.
3> When I try to kill the node process with kill -9 or pkill node nothing happens.
I see the pid for the node process is changing continuously as if it was constantly being restarted. I see posts similar to this but none of them have definitive answers.
I have stopped and started the node site as we all restarting the host. Which I don't like doing as a problem resolution as you don't really know what the underlying problem is.
I also don't see an error log for node.
Any advice or guidance on how to determine what the problem is would be appreciated.

How to stop Yarn Package Manager script from CLI

https://yarnpkg.com/en/docs/cli/
Is there a way to stop what is started from the command "yarn run"? Is my only option to lookup the process number and call kill on it?
The usual way ctrl-c should work. If it doesn't work, than you have bug in the script. The script's author missed handler for shutdown (SIGINT/SIGTERM/etc).
I had a similar issue having it running after ctl+c and then I thought, maybe it is just running on the cache
so went to http://localhost:3000/
ctrl+F5
which forces refresh without cache showed me that the actual project wasn't really running anymore!
;)
*hadn't it worked I would have had to sudo kill the 3000 port
I know this is a well-answered question. However, it behaved once very strange when I was running a sample React code which was auto-created by the create-react-app CLI, on my Windows 10.
After hitting Ctrl+C, which is the most suggested standard way to stop the yarn run, though I got back the command prompt, there was a ghost process lingering around there, which was still actively listening to 3000(default) port, and localhost:3000 was working as normal.
So finally this is how I fixed it:
netstat -ano | grep ":3000" (yeah, I ran this from my git-bash instead of command prompt!)
Noted down the PID of the line where it says LISTENING on 3000
Pressed Ctrl+Shift+Esc to open the Task Manager
Went to the Process tab
Right clicked on one of the headings, say Name
Selected PID --> This added the PID column to the display
Located the PID in question
Right clicked on it and clicked "End task"
Luckily Windows knew how to kill that misbehaving, ghost process and the port became free for me.
NOTE: Prior to the above-mentioned steps, I tried to kill that PID from git-bash using the famous (or notorious as per its meaning?? >8)) kill -9 command. It was responding back with no such PID msg, however netstat -ano was clearly displaying the PID and browser was proving that the ghost process is up and alive!!

jsvc.exec error: Still running according to PID file

Running my Java service using jsvc on Linux (Ubuntu) 10.04.4 LTS and when I stop service and requests and then hung, checked log to find jsvc exec error below.
14/03/2014 12:49:48 19831 jsvc.exec error: Still running according to PID file /home/user/tmp/example.pid, PID is 19728
14/03/2014 12:49:48 19830 jsvc.exec error: Service exit with a return value of 122
Any idea ?
Thanks,
I'm having a similar problem that happens at a log rotation. It appears that the system is shutting down, rotating the logs, then trying to start the system. I believe error 122 is telling you that it hasn't completed shutting down yet and can't restart. I believe the -wait parameter is needed in the start script.
http://commons.apache.org/proper/commons-daemon/jsvc.html
Also see http://freddyandersen.wordpress.com/2009/09/02/running-tomcat-as-a-service-on-linux/ for an example.
If this is happening due to logrotate, use the copytruncate option instead of restarting the service.
http://www.vineetmanohar.com/2010/03/howto-rotate-tomcat-catalina-out/
Try to run below command. Here 19728 is the process id.
pkill -9 19728
Now start your process. It will work.
This will solve your problem.
Thank you.

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