I'm currently attempting to start a project with Compojure.
At this point I am just trying to run the hello world app and see it through the browser.
I have a droplet on Digital Ocean with Ubuntu 13.04 installed and I cannot seem to access the webpage once the server is started.
lein ring server-headless 3000
eg: http://hostname:3000
I just get page not found. I checked to make sure jetty is using port 3000 and it is.
Am I missing dependencies?
I can't think of anything that would prevent me from viewing the page.
*Update: *
If I run the server on port 80 I can see it. I haven't added or configured any firewalls unless the Digital Ocean image comes with one by default.
on the instance run
sudo netstat -np | grep 3000
to see what address your server is listening to, if it is 0.0.0.0 then your server is listening to connections from any source and the problem is with an upstream firewall (most likely) or a local firewall (unlikely). If it is '127.0.0.1or::1/128` then your server is only listening for local connections and you need to change the binding address in the project.clj file, though this is unlikely as binding to any interface by default
Related
I'm a complete newbie when it comes to networking. I have two PCs on my LAN both running Manjaro. My main aim is to test functionality on a Django server running on one PC, from the other. I am running the Django server on the PC with ip address 192.168.1.138 using the command
python manage.py runserver 192.168.1.138:8000
and in settings.py
ALLOWED_HOSTS = ['localhost', '192.168.1.138']
I can ping 192.168.1.138 from the client PC, and ping the client PC from the server PC. But if I enter the ip address/port into the browser, it fails with
took too long to respond
I don't know if this a separate problem or a manifestation of the first, but when I run NitroShare, I am able to 'see' the PC running the Django server from the PC acting as the client, but if I try to transfer a file, again it times out. I am unable to see the client from the server in NitroShare.
Any suggestions or help gratefully received
Ensure you don't have a firewall running (or that it allows connections to port 8000). Manjaro's docs imply there might be no firewall by default, but in case there is, see https://wiki.manjaro.org/index.php?title=Firewalls
Set ALLOWED_HOSTS = ['*'], don't bother with limiting them.
Run with python manage.py runserver 0:8000 ; the 0 stands for 0.0.0.0, i.e. has the server listening on all network interfaces.
First I would scan with the other PC the open ports of you "Server"-PC, you can do that with tools like Nmap. Make sure you opened the ports of your "Server"-PC at your router interface. Another option could be the launching of the django app in a docker container. Here's the link of the official docker image at DockerHub:
https://hub.docker.com/_/django
I just want to see my development working on an EC2, showing to some friends, and think in deploying it after all of the work is done, but react doesn't cooperate. :/
I did everything I always do.
Started a ubuntu server on EC2
applied a group with 3000/tcp opened in my instance
Installed all dependencies of my app, npm 11.1 and its packages via npm install.
npm started it
and...
Nope.. there is no "and"... just my tears over a bunch of attempts without reaching 3000/tcp via public ip and dns..
I even tested ping on it.. set ICMP echo request and response rules, tested and it worked, but when I try to reach the application by 3000/tcp port, nothing.
Does someone have any idea?
As an image talk more than a thousand words, there it is... My nighmare
PS: a curl on localhost:3000 inside the ec2 works just fine.. while
another curl outside the ec2 returns Connection Refused
Looks like the application is bound to localhost (127.0.0.1). Update your start property to include --host 0.0.0.0
Refer: https://github.com/webpack/webpack-dev-server/issues/147
I have a VirtualBox setup with Arch Linux. I use it to run various tutorials on Node.js and Redux. The host OS is Windows 8.1. I've mapped guest port 8080 to host 8080. When I run a simple Node.js server on the VM I can access it from the host machine on this port, just as expected.
Now I need to try another test server (webpack-dev-server). I start it in VM and check that it works via curl, but when I try to access it from the host, it says the connection was reset by peer. curl -v shows a pretty standard log: it sends a header and then says Recv failure. So:
one web server on VM works OK and is accessible via the mapped port;
another web server on VM works OK on VM, but is not accessible via the mapped port.
What could be the cause?
I think it's something with VirtualBox, but just in case I label this with webpack-dev-server as well.
I'm trying to install the enterprise edition of neo4j on an existing EC2 (Amazon linux) instance. So far I've
wget "link to enterprise"
untar the file
renamed and moved the folder to NEO4J_HOME
then went into the config files for neo4j.properties to make the following changes:
# Enable shell server so that remote clients can connect via Neo4j shell.
remote_shell_enabled=true
# The network interface IP the shell will listen on (use 0.0.0 for all interfaces)
remote_shell_host=127.0.0.1
# The port the shell will listen on, default is 1337
remote_shell_port=1337
EDITED Christophe Willemsen pointed out that for my original error, I had forgotten to restart the server at that point but I was still unable to access the web server while it was running. So to make it more clear, I've edited the remaining post:
I went to neo4j-server.properties and uncommented:
org.neo4j.server.webserver.address=0.0.0.0
And start the server
NEO4J_HOME/bin/neo4j 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 -XX:-OmitStackTraceInFastThrow
Starting Neo4j Server...WARNING: not changing user
process [28557]... waiting for server to be ready..... OK.
http://localhost:7474/ is ready.
checking the status:
NEO4J_HOME/bin/neo4j status
Neo4j Server is running at pid 28557
I can run the shell but the when I go to localhost 7474 I still can not connect
Any help would be appreciative. The only tutorial or help I've found assumed I was starting from scratch with a new instance. If someone could provide some instructions for installing or fix my configuration that would be great.
Thanks!
You have to edit neo4j-server.properties and uncomment the line with:
org.neo4j.server.webserver.address=0.0.0.0
So that the db listens on an external interface not just localhost, and you have to open the port (7474) in your firewall rules.
Make sure to secure access to the db though:
http://neo4j.com/docs/stable/security-server.html
I have to do distributed testing using JMeter. The objective is to have multiple remote servers in AWS controlled by one local server send a file download request to another server in AWS.
How can I set up the different servers in AWS?
How can I connect to them remotely?
Can someone provide some step by step instructions on how to do it?
I have tried several things but keep running into connectivity issues across networks.
We had a similar task and we ran into a bunch of issues as well. Here are the details of the whole process and what we did to resolve the issues we encountered. Hope it helps.
We needed to send requests from 5 servers located in various regions of the world. So we launched 5 micro instances in AWS, each in a different region. We chose the regions to be as geographically apart as possible.
Remote (server) JMeters config
Here is how we set up each instance.
Installed java:
$ sudo apt-get update
$ sudo apt-get install default-jre
Installed JMeter:
$ mkdir jmeter
$ cd jmeter;
$ wget ftp://apache.mirrors.pair.com//jmeter/binaries/apache-jmeter-2.9.tgz
$ gunzip apache-jmeter-2.9.tgz;tar xvf apache-jmeter-2.9.tar
Edited the jmeter.properties file in the /bin folder of the JMeter installation and uncomment the line containing the server.rmi.localport setting. We changed the port to 50000.
server.rmi.localport=50000
Started JMeter server. Make sure the address and the port the server reports listening to are correct.
$ cd ~/jmeter/apache-jmeter-2.9/bin
$ vi jmeter-server
Local (client) JMeter config
Then we set up JMeter to run tests remotely on these instances on our local client machine:
Ensured to use the same version of JMeter as was running on the servers. Installed Java and JMeter as described above.
Enabled remote testing by editing the jmeter.properties file that can be found in the bin folder of the JMeter installation. The parameter remote_hosts needed to be set with the public DNS of the remote servers we were connecting to.
remote_hosts=54.x.x.x,54.x.x.x,54.x.x.x,54.x.x.x,54.x.x.x
We were now able to tell our client JMeter instance to run tests on any or all of our specified remote servers.
Issues and resolutions
Here are the issues we encountered and how we resolved them:
The client failed with:
ERROR - jmeter.engine.ClientJMeterEngine: java.rmi.ConnectException: Connection - refused to host: 127.0.0.1
It was due to the server host returning the private IP address as its address because of Amazon NAT.
We fixed this by setting the parameter RMI_HOST_DEF that the /usr/local/jmeter/bin/jmeter-server script includes in starting the server:
RMI_HOST_DEF=-Djava.rmi.server.hostname=54.xx.xx.xx
Now, the AWS instance returned the server’s external IP, and we could start the test.
When the server node attempted to return the result and tried to connect to the client, the server tried to connect to the external IP address of my local machine. But it threw a connection refused error:
2013/05/16 12:23:37 ERROR - jmeter.samplers.RemoteListenerWrapper: testStarted(host) java.rmi.ConnectException: Connection refused to host: xxx.xxx.xxx.xx;
We resolved this issue by setting up reverse tunnels at the client side.
First, we edited the jmeter.properties file in the /bin folder of the JMeter installation and uncommented the line containing the client.rmi.localport setting. We changed the port to 60000:
client.rmi.localport=60000
Then we connected to each of the servers using SSH, and setup a reverse tunnel to port 60000 on the client.
$ ssh -i ~/.ssh/54-x-x-x.us-east.pem -R 60000:localhost:60000 ubuntu#54.x.x.x
We kept each of these sessions open, as the JMeter server needs to be able to deliver the test results to the client.
Then we set up the JVM_ARGS environment variable on the client, in the jmeter.sh file in the /bin folder:
export JVM_ARGS="-Djava.rmi.server.hostname=localhost"
By doing this, JMeter will tell the servers to connect to localhost:60000 for delivering their results. This ends up being tunneled back to the client.
The SSH connections to the servers kept dropping after staying idle for a little bit. To prevent that from happening, we added a parameter to each of the SSH tunnel set up directing the client to wait 60 seconds before sending a null packet to the server to keep the connection alive:
$ ssh -i ~/.ssh/54-x-x-x.us-east.pem -o ServerAliveInterval=60 -R 60000:localhost:60000 ubuntu#54.x.x.x
(.ssh/config version of all required SSH settings:
Host 54.x.x.x
HostName 54.x.x.x
Port 22
User ubuntu
ServerAliveInterval 60
RemoteForward 127.0.0.1:60000 127.0.0.1:60000
IdentityFile ~/.ssh/54-x-x-x.us-east.pem
IdentitiesOnly yes
Just use ssh 54.x.x.x after setting this up.
)
I just went though this on openstack and found the same issues... no idea why the jmeter remoting documentation only covers half the required steps. You can do it without tunnels or touching the properties files.
You need
All nodes to advertise their public IP - on AWS/OS this defaults to the private IP
Ingress rules for the RMI port which defaults to 1099 - I use this
Ingress rules for the RMI "local" port which defaults to dynamic. Below I use 4001 for the client and 4000 for servers. The port can be the same but note the properties are different.
If you are using your workstation as the client you probably still need tunnels. Above Archana Aggarwal has good tips for tunnels.
Remote servers
Set java.rmi.server.hostname and server.rmi.localport inline or in the properties file.
jmeter-server -Djava.rmi.server.hostname=publicip -Dserver.rmi.localport=4000
Sneaky server on client
You can also run one on the same machine as the client. For clarity I've set java.rmi.server.hostname but left server.rmi.localport as dynamic
jmeter-server -Djava.rmi.server.hostname=localip
Client
Set java.rmi.server.hostname and client.rmi.localport inline or in the properties file. Use -R etc like so:
jmeter -n -t Test.jmx -Rremotepublicip1,remotepublicip2 -Djava.rmi.server.hostname=clientpublicip -Dclient.rmi.localport=4001 -GmypropA=1 -GmypropB=2 -lresults.jtl
When you go for distributed testing using JMeter in AWS, I would suggest you to use docker - which will help us with jmeter test infrastructure very quickly. This way we can also ensure that same version of java and jmeter are installed in all the instances of amazon which is very important of JMeter distributed testing.
Ensure that - you set below properties and ports are open for jmeter-server. [they do not have to be 1099,50000 exactly]
server.rmi.localport=50000
server_port=1099
java.rmi.server.hostname=SERVER_IP
for client
client.rmi.localport=60000
java.rmi.server.hostname=SERVER_IP - this step is very important as the container in aws instance will have their own IP address in the docker network - so master and slave can not communicate. So we explicitly set this property
More info:
http://www.testautomationguru.com/jmeter-distributed-load-testing-using-docker-in-aws/